Steelmaking

What Is Basic Oxygen Steelmaking?Steel is one of the world’s most important materials. Consisting of iron and carbon, it’s an alloy that’s used to make everything from screws and bolts to bridges, buildings, vehicles, engines and more. While there are different techniques used to produce steel, the most common is known as basic oxygen. Basic oxygen steelmaking accounts for over half of the world’s steel. What is basic oxygen steelmaking oxygen?Overview of Basic Oxygen SteelmakingBasic oxygen steelmaking is a multistep process that involves the use of pure oxygen to produce steel from molten iron. Also known as oxygen conversion steelmaking, it leverages oxygen to change the carbon ratio of steel. Basic oxygen steelmaking involves blowing pure oxygen into molten pig iron. With a higher oxygen content, the ratio of carbon to other elements — including iron — drops.Steps to Performing Basic Oxygen SteelmakingHow is basic oxygen steelmaking performed? This common steelmaking process begins with pig iron. The pig iron is smelted in a blast furnace, after which it’s poured into a ladle. From there, it’s blasted with oxygen as a form of pretreatment. The next step of basic oxygen steelmaking involves charging.Charging involves filling the furnace with ingredients. As you may know, steel contains more than just iron; it contains carbon, and in some cases, other elements. These ingredients are added to the furnace during basic oxygen steelmaking.Now it’s time for the pure oxygen. The molten steel-filled vessel is raised and exposed to a lance that contains about a half-dozen nozzles, after which it’s injected with pure oxygen. The multi-nozzle lance essentially blows pure oxygen over the molten steel, thus allowing the carbon to dissolve while simultaneously creating excessively high temperatures. This step, in fact, can produce temperatures of over 3,000 degrees Fahrenheit.Fluxes are then added to the steel-filled vessel, which are responsible for the slag. The slag essentially absorbs impurities from the steel. The slag is then separated from the steel. Lastly, the steel is allowed to cool. There are different types of basic oxygen steelmaking, but most of them involve these steps.In ConclusionBasic oxygen steelmaking is a process for producing steel. It uses pig iron, carbon and pure oxygen. With these three elements, steel is produced in a vessel. It’s called “basic oxygen steelmaking” because it uses “bases.” The bases are slag, which as previously mentioned, help to absorb and remove impurities from the steel. 

GRADES OF HOT ROLLED STEELWhen it comes to an excellent combination of mechanical properties such as tensile strength, shear strength, toughness, hardness, and ductility, it is hard to beat carbon steel. When it comes to having all of those mechanical properties at an affordable rate, it is hard to beat hot rolled carbon steel. Hot rolled carbon steel is a metal alloy comprised mostly of iron with some carbon that is rolled down in size from an ingot, at a heat level above its recrystallization temperature. Forming hot rolled carbon steel at this high temperature gives it excellent mechanical properties while keeping costs lower than a cold-rolled carbon steel. There are many grades of hot rolled carbon steel available, which might raise the question: “What is the difference among all of the hot rolled steel grades?” This article answers that question. The following are some common Grades of Hot Rolled Steel:A36C1010C1018A1011C1026A500C1045C1141 A36ASTM A36 steel is one of the most popular hot rolled steels that Metal Supermarkets sells. When it comes to hot rolled steel, Metal Supermarkets carries product with designations from two organizations: the American Iron and Steel Institute (AISI) and the American Society for Testing and Materials (ASTM). A36 is an ASTM-designated material. It is considered a low carbon steel, since its carbon content is generally between 0.25% and 0.29% by weight. The “36” in A36 is significant in that it specifies the minimum yield tensile strength at 36,000 psi. A36 is very machinable, weldable, and has excellent mechanical properties. This is part of the reason it is so popular, and why it is widely used in structural applications. Metal Supermarkets sells ASTM A36 in round bar, rectangular bar, square bar, channel, angle, plate, tread plate, round tube, and shafting. C1010 and C1018AISI C1010 and AISI C1018 are two hot rolled steels that are very similar. They are both low carbon. In fact, the only noticeable difference between their chemical compositions is their carbon content. C1010 is 0.08% to 0.13% carbon by weight and C1018 is 0.14% to 0.20% carbon by weight. The difference in carbon content between them can result in slight variations to ductility and tensile strength, but for the most part they are quite similar. They are both weldable, machinable, and formed relatively easily when compared with alloy and high carbon steels. Metal Supermarkets provides C1010 in round tube and C1018 in round bar and mesh sheet. C1010 and C1018 are widely used in structural applications, and are also used frequently in the automotive and furniture industries. A1011A1011 is another ASTM-designated hot rolled steel that Metal Supermarkets offers. This grade can also have small amounts of other trace elements that make it a very versatile steel. It is widely used in sheet steel structural applications, automotive bodies, drums, and general metal fabrication. Metal Supermarkets provides A1011 in the flat sheet form as well as the expanded metal form. C1026C1026 is an AISI-designated steel that very closely mimics the ASTM-designated A36 steel mentioned above. Their chemical properties have a lot of overlap, with their carbon contents both being on the upper limit of what constitutes a low carbon steel. AISI 1026 has a target carbon content of 0.22% to 0.26% by weight. When they are both in the hot rolled condition, their mechanical properties are quite similar as well. Both AISI C1026 and ASTM A36 are great choices when a hot rolled steel is needed, with more strength than an A1011, C1010, or C1018 can provide. AISI C1026 is used for structures, automotive components, and furniture, to name a few areas where this hot rolled steel is used. C1026 is available from Metal Supermarkets in square tube and rectangular tube. A500ASTM A500 is another low carbon hot rolled steel. It can have up to 0.26% carbon by weight in its chemical composition, and is quite similar to ASTM A36. One main difference between ASTM A500 and ASTM A36 is the shape in which each type of hot rolled steel is available. As previously mentioned, A36 is available in round bar, rectangular bar, square bar, channel, angle, plate, tread plate, round tube, and shafting. A500, on the other hand, is solely used for tubing. Metal Supermarkets carries A500 in square and rectangular tubing in particular. Applications for ASTM A500 are similar to other low carbon hot rolled steels; they are used abundantly in structural applications. C1045C1045 is another AISI designated hot rolled steel. What makes this hot rolled steel different from the previously mentioned steels is that it is a medium carbon steel. With 0.42% to 0.50% carbon by weight, it generally provides more strength than low carbon hot rolled steels. C1045 also has enough carbon where it becomes quite receptive to heat treating. This means that through quench hardening and annealing, its mechanical properties can be altered. C1045 is used in applications similar to low carbon hot rolled steel, except it is typically preferred to low carbon steel when strength is more of a concern than ductility. Metal Supermarkets sells AISI C1045 in the form of round bars and plate. C1141AISI C1141 is another medium carbon hot rolled steel, similar to C1045. However, AISI C1141 has additions of sulfur and manganese that give it different properties. First, heat treating can be more effective on C1141 than C1045. Second, C1141 is considered a free machining steel. This means that it is easier on machining tools, which is important as carbon content increases because the corresponding increase in hardness can hinder machinability. It is important to note, however, that the additions of sulfur that make C1141 easily machinable also make it unweldable, in general. AISI C1141 is available in shafting and round bar forms from Metal Supermarkets. AISI C1141 is frequently used in components that require a lot of machining and in certain types of fasteners.

What Is Basic Oxygen Steelmaking?Steel is one of the world’s most important materials. Consisting of iron and carbon, it’s an alloy that’s used to make everything from screws and bolts to bridges, buildings, vehicles, engines and more. While there are different techniques used to produce steel, the most common is known as basic oxygen. Basic oxygen steelmaking accounts for over half of the world’s steel. What is basic oxygen steelmaking oxygen?Overview of Basic Oxygen SteelmakingBasic oxygen steelmaking is a multistep process that involves the use of pure oxygen to produce steel from molten iron. Also known as oxygen conversion steelmaking, it leverages oxygen to change the carbon ratio of steel. Basic oxygen steelmaking involves blowing pure oxygen into molten pig iron. With a higher oxygen content, the ratio of carbon to other elements — including iron — drops.Steps to Performing Basic Oxygen SteelmakingHow is basic oxygen steelmaking performed? This common steelmaking process begins with pig iron. The pig iron is smelted in a blast furnace, after which it’s poured into a ladle. From there, it’s blasted with oxygen as a form of pretreatment. The next step of basic oxygen steelmaking involves charging.Charging involves filling the furnace with ingredients. As you may know, steel contains more than just iron; it contains carbon, and in some cases, other elements. These ingredients are added to the furnace during basic oxygen steelmaking.Now it’s time for the pure oxygen. The molten steel-filled vessel is raised and exposed to a lance that contains about a half-dozen nozzles, after which it’s injected with pure oxygen. The multi-nozzle lance essentially blows pure oxygen over the molten steel, thus allowing the carbon to dissolve while simultaneously creating excessively high temperatures. This step, in fact, can produce temperatures of over 3,000 degrees Fahrenheit.Fluxes are then added to the steel-filled vessel, which are responsible for the slag. The slag essentially absorbs impurities from the steel. The slag is then separated from the steel. Lastly, the steel is allowed to cool. There are different types of basic oxygen steelmaking, but most of them involve these steps.In ConclusionBasic oxygen steelmaking is a process for producing steel. It uses pig iron, carbon and pure oxygen. With these three elements, steel is produced in a vessel. It’s called “basic oxygen steelmaking” because it uses “bases.” The bases are slag, which as previously mentioned, help to absorb and remove impurities from the steel. 

The difference about Cast and Forged Steel Steel products may be manufactured either by casting or forging steel. Steel casting is the process by which a metal is heated until it reaches a liquid state and then poured into a mold that shapes the desired product. Steel forging implies the application of mechanical forces to heated solid blocks of steel (such as ingots and/or billets) that are shaped into desired products permanently. STEEL FORGING VS. CASTINGBoth manufacturing processes require the application of high temperatures to steel raw materials (to liquify or make it malleable) and the execution of CNC machining work at the end of the process to obtain the final product.Final products may also undergo surface finish treatment, such as painting, powder coating, polishing, various types of coating (for example zinc plating) and wear protection/hardening (application of tungsten carbide overlay).Last but not least, cast and forged parts may be assembled, welded, brazed, hard-faced before being shipped as final products.The products resulting from casting and forging processes have different properties in terms of surface porosity (generally better for forged vs. cast products), grain structure (finer for forged products), tensile strength (generally superior for forged products) and fatigue resistance.These alternative manufacturing processes are therefore used (and suited for) different circumstances and applications. The casting process is preferred for:· parts and components that would be too complex or expensive to manufacture by steel forging (example: large valve bodies);· parts that have internal cavities;· large sized parts (there are virtually no size limits in terms of the weight of the parts that can be produced with the casting process);· parts in special alloys (some specific alloys are more difficult to forge than cast, for example, those with a high content of Nickel and Moly, which have considerable resistance to mechanical forces);· parts requiring mass production and small lots.The forging process is preferred for:· parts requiring extremely high strength, toughness, and resistance (indeed, during the forging process the steel grain structure gets modified to conform to the shape of the final product – with high uniformity of composition and metallurgical recrystallization);· parts that have to withstand stronger impacts and mechanical forces;· parts where porosity, the risk of a gas void, pockets and the possible formation of cavities (even micro-granular) are not acceptable;· production of mechanically strong parts without using expensive alloys;· parts that require high wear resistance;· parts subject to high loads and stress;· high-end applications when the integrity and the quality of the part is the main objective in the production process, rather than time and cost.The evolution of the casting technologies has reduced the gap between the physical properties of cast vs. forged products making modern cast products very competitive in terms of quality, strength, and wear resistance: however, in many fields, steel forging remains, still, the preferred manufacturing option (example: small sized valves, i.e. forged valves, or high-pressure valves). STEEL CASTINGThe main types of casting processes are:SAND CASTINGSand casting is the most traditional casting method and consists in pouring liquid metal into binders that resist the molten metal (such as clay bonded/green sand hard bonded/resin, thermosetting resin sand, and shell). INVESTMENT CASTINGThis term refers to precision molding executed by injecting the liquid metal into a metal die and a ceramic coating. The mold material can be hard wax, lost wax, lost foam and similar. These processes are used for different applications in terms of parts dimension (sand casting is used for large parts, investment casting for small parts up to 100 kilograms and 1,5 meters of max. length), allowed tolerances (investment casting create more precise parts) and cost targets (investment castings tend to be more economical than sand casting).STEEL FORGINGSteel forging appeared in China in the ancient ages to produce various types of metal products.Whereas the procedures and the tools used to produce forged parts have changed through the centuries (from the use of anvils, hammers, and manpower to automated machines as hydraulic presses) the basic steel forging process is still based on the application of thermal energy to solid blocks of steel and their further processing into finished products by the application of mechanical (hammering) forces.FORGING PROCESSThe basic process of forging consists of a few traditional steps:1. the raw material (steel blocks, ingots, billets) is cut into smaller parts if needed2. the raw material is heated to reach the required forging temperature (the application of heat is necessary to make the material ductile and malleable); the forging temperature depends on the type of metal and is achieved by positioning the material into a furnace/oven;3. the heated metal is shaped into the required form by applying mechanical forces (pressure).4. the semifinished part undergoes machining, finishing and heat treatmentAt the end of the process, the resulting product features extreme strength, impact toughness and wear resistance thanks to the metallurgical recrystallization and grain refinement resulting from the applied thermal and mechanical treatment.Depending on the temperature applied to the raw material during the forging process, forging is classified into:· Cold forging steel: when no heating is applied, i.e. the forging process happens at room temperature (higher mechanical forces are needed in this case and the metal has lower formability vs. hot or warm forging methods)· Warm forging steel: the raw material is heated at temperatures between 800 and 950/1000 C°· Hot forging steel: when the heating temperature is above 950/1000 C° (and generally below 1300 C°) to give the metal high ductility and make the forging possible even with the application of modest mechanical pressures.TYPES OF STEEL FORGINGCLOSED-DIE FORGINGThe “Closed Die Forging Steel” is a forging process in which the dies move towards each other and covers the workpiece in whole or in part. The heated raw material, which is approximately the shape or size of the final forged part, is placed in the bottom die.OPEN-DIE FORGINGThe “Open die forging steel” is the process of deforming a piece of metal between multiple dies that do not completely encapsulate the material. The metal is shaped by the action of the dies that “hammer” or “stamp” the material through a series of movements until the required shape is achieved.OPEN-DIE VS. CLOSED-DIEFIELDS OF APPLICATION OF STEEL CASTING AND FORGINGSteel casting and forging are used to produce parts for the following industries:· petrochemical plants (example forged valves, forged fittings, flanges, etc)· power generation and waste processing· mining and mineral processing· agriculture and livestock handling· water treatment· aeronautics· automobile industry (pulleys and gear wheels)· materials handling· brickworks· asphalt plants· stormwater parts· rendering plants· railways 

How does heating the metal affects its properties?Heat can affect the electrical, magnetic, and structural properties of metals. Since metal has a wide range of uses, various conditions emphasize different attributes. Toughness is required in industrial applications, whereas low electrical density is significant in electronic applications.There are many methods of heating metal that are widely used to change these properties. To obtain the desired result, the temperature at which the metal is heated and the rate at which it cools is closely regulated. The following are the most critical ways that metals are converted by heat:MagnetismElectrical ResistanceThermal ExpansionMagnetismIron, nickel, and cobalt are the three metals that have magnetic properties. It is referred to as ferromagnetic metal. Heating these metals reduces their magnetism to the point that magnetism is no longer there. The Curie temperature is the temperature at which this happens. This temperature is 626 ° Fahrenheit for nickel, 2,012 degrees Fahrenheit for cobalt, and 1,418 ° Fahrenheit for iron. Electrical ResistanceThe electrical resistance of a metal is an indicator of how deeply it obstructs the flow of electrical current. Electrons scatter when they collide with the metallic structure as they flow through the metal. Electrons consume more energy and travel faster while the metal is heated. This causes further scattering, which raises the sum of the resistance. Thermometers typically calculate temperature by measuring the difference of electrical resistance in a piece of wire. Thermal ExpansionWhen heated, metal expands. Temperature causes an increase in length, surface area, and thickness. Thermal expansion is the technical name for this. The degree of thermal expansion varies depending on the metal. Thermal expansion happens as a result of heat increasing the motions of the metal’s atoms. When building metallic structures, it is critical to account for thermal expansion. A simple example is the construction of household pipes, which must allow for expansion and contraction as the seasons shift. Heat Treatment on metalsHeat treatment is a method of altering the characteristics of metal in order to make it more suitable for its desired applications. The following are the most common methods of heat treatment: AnnealingNormalisingHardeningTemperingAnnealingMaterials such as iron, steel, copper, brass, and silver are commonly softened by annealing. The procedure entails heating the material to a certain degree and then allow to cool slowly and steadily. Annealing changes the metal’s physical and chemical characteristics to make it more ductile and less rigid. This makes for easier carving, stamping, and formation methods, as well as easier cutting of the metal. Electrical conductivity is also improved by annealing. NormalizingNormalizing also known as normalization is a process used to achieve uniformity of grain size and composition in alloys. The metal is heated to a certain degree before being cool by air. The resulting metal is free of impurities and has increased strength and hardness. Normalizing is often used to manufacture harder and tougher steel, but it is less ductile than annealing. Since the procedure improves this attribute, the normalizing process is typically done on products that may be exposed to machining. HardeningSteel and other alloys are hardened to enhance their mechanical property. During hardening, the metal is heated to a high temperature and kept there until a proportion of the carbon has been melted. The metal is then put out, which means it is quickly cooled in oil or water. Hardening results in an alloy with high strength and wear-resistant. Hardening, on the other hand, makes it more brittle and is thus unsuitable for industrial application. Surface hardening is used where the surface of a part has to be hard enough to prevent wear and degradation while preserving ductility and resilience to withstand impact and shock loading. TemperingTempering is used to increase the ductility of steel. Untempered steel is very strong, but it is too porous for the majority of practical applications. Tempering is a low-temperature heat treatment technique used to achieve a desired hardness/toughness ratio after hardening (neutral hardening, double hardening, ambient carburizing, carbonitriding, or induction hardening). To reduce some of the excess hardness, steel is heated to a lower temperature. After that, the metal is able to cool in still air, resulting in a harder and less brittle material.

All you need to know about The Melting Points of MetalsMetals have prestige for being able to survive harsh environments. Heavy loads, continuous cycling, major intensity, caustic conditions, and even extreme temperatures are all factors to consider. Furnaces, diesel motors, piston engines, spark nozzles, high-speed machines, and exhaust systems are all exposed to conditions that can melt some metals. When choosing a metal for a high application various temperature points must be considered, with the melting temperature of the metal being one of the most significant. What is the melting point of metals?The melting temperature of a metal, also known as the melting point, is the temperature at which it starts to transition from a solid to a liquid state. A metal’s solid and liquid states are in balance at melting temperature. If this temperature is reached, heat may be applied to the metal indefinitely without raising the total temperature. Additional heat can help to increase the heat of the metal until it is fully in the liquid process. What Is the Importance of Metal Melting Temperature?There are many significant levels that a metal achieves when it is heated during a metalworking operation or as a result of the usage but one of the main values is the melting temperature of the metal.The part loss that will happen once a metal exceeds its melting point is one of the reasons why the melting temperature is so significant. Metal failure occurs before the melting point but once a metal approaches the melting peak and starts to melt, it no longer serves its desired intentFor eg, once a furnace element starts melting the furnace can no longer operate if the component is essential. When a jet engine’s fuel nozzle melts, the orifices plug up and the engine becomes inoperable. It is necessary to remember that other forms of metal loss, such as creep-induced cracks, will occur long before the melting temperature is reached, and studies on the impact of the different temperatures to which metal would be exposed must be performed ahead of time.A factor that a metal’s melting point is so essential because metals are moldable while they are molten. Metals are heated to freezing temperatures in a variety of processing processes. Metals must be liquids for smelting, fusion welding, and casting to take place. While doing a production process in which metal will be heated, it is important to know the temperature at which this will occur so that the right materials for the machinery used can be chosen. A welding gun must endure the atmospheric heat of an electric current and molten metal. Melting Points of Common MetalsAluminum: 660°C or 1220°FBrass: 930°C or 1710°FGold: 1063°C or 1945°FSilver: 961°C or 1762°FCarbon Steel: 1425-1540°C or 2597-2800°FStainless Steel: 1375 – 1530°C or 2500-2785°FInconel: 1390-1425°C or 2540-2600°FCast Iron: 1204°C or 2200°FLead: 328°C or 622°FMolybdenum: 2620°C or 4748°FNickel: 1453°C or 2647°FAluminum Bronze: 1027-1038°C or 1881-1900°FChromium: 1860°C or 3380°FCopper: 1084°C or 1983°FPlatinum: 1770°C or 3218°FTungsten: 3400°C or 6152°FZinc: 420°C or 787°FTitanium: 1670°C (3038°F)

Difference between Annealing and TemperingThe difference between annealing and tempering is determined by how it is treated. Tempering the metal entails heating it to a certain heat below a certain threshold and then cooling it at a very slow and regulated rate, while annealing involves heating the metal to a given temperature and then cooling it at a very slow and controlled rate, and is often performed in air, vacuum, or inert atmospheres. What is Heat Treatment on metals?Heat treatments are used to modify the Mechanical-Property, Physical-Property of the metal metals without altering their appearance. They are critical processes in metal production that improve the favorable properties of metal while allowing for more processing.The heat and temperature of metal are closely regulated in various heat treatment processes. For instance, steel is a metal that mostly goes under heat treatment for various commercial uses.Common objectives of heat treatment are to: Increase strengthImprove elasticityImprove machiningIncrease hardnessImprove formabilityIncrease ductilityImprove toughnessThe cooling stage has varying results depending on the metal and phase. Steel hardens as it is easily cooled, while aluminum softens during the fast cooling stage of solution annealing. There are various methods through which metals are given heat treatment, but Annealing and Tempering are commonly used methods. What Is Annealing?Annealing is the process in which the steel is heated at a certain degree and then cooled slowly at a regulated pace.Annealing is sometimes used to: Prepare metal for cold working by softening it.Increase electrical conductivity.Increase machinabilityFor restoring the metal ductility annealing is done. Cold welding hardens the metal in such a way that, excessive work on it, which may break or crack the metal. Since annealing releases mechanical stresses created during machining or grinding, cold working may take place without the risk of cracking. Annealing is mostly used for steel, but some metals such as copper, aluminum, and brass may be solution annealed. For the annealing process of steel, huge ovens or heaters are used. There must be enough space in the ovens so that it allows proper air to flow through the metal. Gas fire conveyor-furnace are utilized for huge metals parts, and Cars bottoms furnace is used for the small parts of metals. The metal is heated to a certain temperature during the annealing process, where recrystallization can occur. Any imperfection found due to distortion is fixed at this level. The metal is been allowed to set to a certain degree and been cooled at room temperatures. To achieve a refined microstructure and thus maximize softness, the cooling process must be carried out very slowly. This is often accomplished by immersing the hot steel in sand, ashes, or other low heat conductivity materials, or by turning off the oven and allowing the steel to cool with the furnace. What is tempering?Tempering is a technique applicable to improve the hardness of alloys having alloys, especially steel. While steel which is not tempered is extremely stiff, it is too fragile for most applications. Tempering is widely used to reduce excess stiffness after hardening.Tempering is used to modify: FortitudeThe degree of difficultyStability of the structureDuctility is a term that refers to the ability to tenacity. Tempering is the process of heating a metal to a specific temperature less than the critical points, which is mostly found in air, vacuum, or inert atmospheres. The temperature is changed based on how much hardness has to be minimized. Although it varies depending on the metal, in general, low temperatures decrease brittleness while retaining the majority of the hardness, while higher temperatures reduce hardness, increasing elasticity and plasticity while causing some yield and tensile strength to be lost. It is necessary to keep on heating steadily which does not crack steel or other metals. The metal is held to a certain degree for a fixed time. The interior pressure within the metals is been relaxed at the time. Then the metal soon cools in the air or in room temperature.

Measuring Metal Strength : Tensile Strength and Impact StrengthTensile strength and impact strength are two of the most important factors to consider when choosing a metal for a particular project, particularly when it comes to structural applications. It’s critical to understand these mechanical properties and how to test them before choosing the right metal for your project. What Is Tensile Strength?Tensile strength is a measurement of a metal’s resistance to deformation and failure as it is subjected to loads that tear it apart (known as tensile loads). The tensile strength of a material is usually measured in pounds per square inch (PSI) or Pascal (Pa). Tensile strength is of 3 types that is : Tensile Yield Strength.Ultimate Tensile Strength.Fracture Tensile Strength.The yield strength of a metal is the strength it has until it starts to deform plastically. The ultimate tensile strength of a metal is its highest tensile strength, which is normally discovered after plastic deformation has begun. The strength of the metal at the point of final failure is known as fracture tensile strength. Testing Tensile Strength:A tensile testing machine is needed to better measure the tensile strength of a material. This machine is made up of two sets of jaws, a control unit, and cylinders that generate tensile load power. A metal specimen is loaded into the jaws to perform the examination. In most cases, the metal is machined to be stronger where the jaws clamp it than it is in the middle. The control unit activates the cylinders, and one or both sets of jaws begin to shift away from one another, causing the metal to tensile. Data on how much force was used is retrieved from the control device until the material reaches its point of failure.The force data is then combined with the area of the metal’s cross section to determine the force over area unit, such as PSI or Pa. A stress-strain curve can be used to show the tensile test results. Since so many metals are subjected to a tensile load during their service life, tensile strength is a mechanical property that is commonly recorded. Chains for lifting or towing, fasteners when tightened, or structural metals in a skyscraper when the wind adds weight to the structure are some functional cases where tensile strength is a critical factor. What is the concept of impact strength?The power of a metal to withstand collision energy while preventing cracking or fracture is referred to as impact strength. Impact strength, also referred to as hardness, is usually measured in Foot -Pounds or ft-lbf else by Joules per metre or J/m. Testing Impact StrengthImpact Strength can be measured in a variety of ways. The Charpy V-notch test is one of the most often used method of testing. A metal specimen is machined to a size determined by a standard and a notch precision machined into the middle to perform a Charpy V-notch examination. This functions like a geometric stress concentrator, causing the substance to crack in the exact spot desired during testing. This notch must be machined with great precision because it is critical for retrieving correct test data.A Charpy V-notch tester is then used to analyse the metal sample. The Charpy V-notch tester consists of a specimen vice and a horizontally positioned pendulum with a known weight. The pendulum is released during the measurement, and the energy consumed by the metal as the pendulum hits and deforms it is measured. The amount of energy consumed is then combined with the metal’s dimensional values to determine the metal’s impact power. This test is often performed at a variety of temperatures because temperature has a significant influence on metal impact ability. The Izod impact strength test is another choice for determining hardness. Since metals are exposed to crashes and impacts – even if unintentional – in too many applications, impact strength is a significant mechanical property to understand. A hammer head colliding with an individual, stamping dies, and chisels are all examples of impact stresses applied to metals.

What Exactly Is Weathering Steel And What Are Its Application?Weathering steel is a type of low carbon steel that incorporates additional alloying elements in addition to carbon and iron atoms. Weathering steel has greater strength and corrosion resistance than normal low carbon steel grades owing to the inclusion of these alloying components. As a result, weathering steel is often used in outdoor installations or areas where regular steel will rust. CompositionWeathering steel, as a low carbon steel, usually absorbs less than 0.3 percent carbon by weight. The low amount of carbon allows it to remain hard and malleable. Corrosion resistance, high strength are the important alloying elements of these steel types. Nickel, Copper and Chromium are the 3 important alloying materials in installations weathering steel. How does Weathering Steel work?Weathering steel is not the same as other corrosion-resistant steels, such as austenitic stainless steel, which resists the accumulation of rust. Weathering steel can rust, but only on the outer surface. If the exterior coating of rust has grown, the rust does not reach further into the weathering steel. The rusty surface coating serves as a shield, shielding the steel from further corrosion. The rust layer formed in the plain carbon steel is porous and breaks off, so it allows another layer to form deeper into the material. The cycle goes on till the steel is useless. The first layer rust on the metal forms to hold on to the steel because of contribution of alloys. Hence there is no need to coat the metal with protective layer. Grade of weathering steelWeathering steel is from a low carbon alloy steel that consists of various grades. Some classes, such as CORTEN A and CORTEN B, are proprietary. Patinax weathering steels are a different kind of patented grade. Many of these patented ratings refer to ASTM classifications A 242 and A 588. What are the applications of Weathering Steel?Weathering steel is widely used for exposed steel buildings because it outlasts plain carbon steel under outdoor environments. This eliminates the need for steel repainting and recoating on a regular basis. Building and bridge design are two examples. The defensive rust coating reduces the corrosion rate to the point that, by the time the level of corrosion becomes dangerous, the structure has already outlived its design life for other reasons. Weathering steel can not be used in such situations because the corrosion resistance is inadequate to survive the conditions. Weathering steel can not be used in areas containing elevated levels of chlorine so the defensive corrosion coating would be unable to tolerate the high levels of corrosives current. As a result, the system will fail prematurely. Weathering steel should not be used in applications that could result in galvanic corrosion or corrosion caused by extreme pH levels.

WHAT IS QUENCHING?Heat treatment is a popular way to alter the mechanical properties of certain metals. Being able to change the hardness, toughness, and strength of a metal while keeping its chemical composition intact and virtually unaltered is a great way to tailor a metal to the needs of the environment and the demands of the job in which the metal is being used. There are many different ways to heat treat metal, one of the most popular ways is through a method known as quenching. What is Quenching?Quenching is a type of metal heat treatment process. Quenching involves the rapid cooling of a metal to adjust the mechanical properties of its original state. To perform the quenching process, a metal is heated to a temperature greater than that of normal conditions, typically somewhere above its recrystallization temperature but below its melting temperature. The metal may be held at this temperature for a set time in order for the heat to “soak” the material. Once the metal has been held at the desired temperature, it is quenched in a medium until it returns to room temperature. The metal also may be quenched for an extended period of time so that the coolness from the quenching process is distributed throughout the thickness of the material. Quenching MediaThere are a variety of quenching media available that can perform the quenching process. Each media has its own unique quenching properties. Considerations for the type of media use include quenching speed, quenching media environmental concerns, quenching media replacement, and quenching media cost. Here are the main types of quenching media: AirOilWaterBrineAirAir is a popular quenching media used to cool metals for quenching. Affordability is one of the main benefits of air; its affordability is a result of its profusion on earth. In fact, any material that is heated and then allowed to cool to room temperature simply by being left alone is considered to have been air quenched. Air quenching is also more intentionally performed when it is compressed and forced around the metal being quenched. This cools the part more rapidly than still air, although even compressed air may still cool many metals too slowly to alter the mechanical properties. OilOil is able to quench heated metals much more rapidly than compressed air. To quench with oil, a heated part is lowered into a tank that is filled with some type of oil. The oil can also be flushed through the part. Different types of oil are often used depending on the application because of their varying cooling rates and flash points. WaterWater is able to quench heated metals rapidly as well. It can cool a metal even faster than oil. In a fashion similar to oil quenching, a tank is filled with water and the heated metal is submerged in it. It can also be flushed through a part. One benefit of water is that flammability of the media is not a concern. BrineBrine is a mixture of water and salt. Brine cools faster than air, water, and oil. The reason for this is that the salt and water mixture discourages the formation of air globules when it is placed in contact with a heated metal. This means that more of the surface area of the metal will be covered with the liquid, as opposed to air bubbles. Quench Hardening SteelSteel deserves a special mention when the quenching process is being discussed because its mechanical properties are very sensitive to quenching. Through a quenching process known as quench hardening, steel is raised to a temperature above its recrystallization temperature and rapidly cooled via the quenching process. The rapid quenching changes the crystal structure of the steel, compared with a slow cooling. Depending on the carbon content and alloying elements of the steel, it can get left with a harder, more brittle microstructure, such as martensite or bainite, when it undergoes the quench hardening process. These microstructures result in increased strength and hardness for the steel. However, they do leave the steel vulnerable to cracking and with a large reduction in ductility. For this reason, some steels are annealed or normalized following the quench hardening process.

WHAT IS WHITE RUST?Galvanizing is a coating process that protects an underlying steel from rust using a protective layer of zinc. However, it is possible for this zinc to form its own kind of “rust”, known as white rust. What Is White Rust?White rust is a white, chalky substance that can form on the surface of zinc materials, like galvanized steel. White rust can form when zinc is exposed to hydrogen and oxygen. This combination creates a zinc hydroxide, as opposed to the iron oxide which is common form of rust. While it can form on any zinc material or zinc-coated material, white rust is a frequent problem for galvanized steel. How Does White Rust Form?White rust forms when zinc is in an environment with hydrogen and oxygen. Most frequently, it occurs when a freshly galvanized material is placed into contact with water, or hydrogen dioxide. White rust is especially likely to form on newly galvanized material. This is because the new zinc coating has not yet had the chance to form the stable oxides, and the hydrogen and the oxygen bond with the pure zinc which forms zinc hydroxide. White rust can be common on galvanized sheet that is being stored, as condensation can become trapped between the individual sheets, leading to the formation of white rust. Is White Rust Bad?While not always the case, white rust on a zinc or zinc-coated material can render the coating useless. Unlike stable zinc oxides, zinc hydroxides do not adhere to other materials well. This means it can flake off and leave the base material exposed. White rust is also generally considered less appealing from a visual standpoint. How to Prevent White Rust?There are several ways to prevent the formation of white rust: Eliminate exposure to waterEliminate the formation of condensationAllowing the zinc to form stable oxidesUsing passivating chemicals or oilsA method that can be used to prevent white rust involves eliminating or greatly reducing the exposure of the zinc or zinc-coated material to water. This can be achieved by increasing the airflow around the zinc material, increasing the temperature of the zinc, or by controlling the humidity in the room where the zinc is placed. Another way to prevent white rust is to avoid bringing cold zinc material into a warm environment as this can cause water to condense and rest on the zinc. This water can then lead to the formation of white rust. Another technique to stop white rust from forming is by ensuring that stable oxides have formed on the surface of the zinc prior to exposing it to wet or other hydrogen-rich environments. When stable zinc oxides have formed, the zinc is far less likely to become zinc hydroxide. To do this, simply let the zinc age for a while in an environment without too much humidity. Increasing the amount of carbon dioxide in contact with the zinc also speeds the formation of stable zinc oxides. One more procedure that can be used to prevent white rust consists of coating the zinc or zinc-coated material with a passivating chemical or oil. A passivating chemical will prevent the oxidation of the zinc, although typically only for a short time. The oil creates a barrier between the zinc and the water, thus lowering the chances of zinc hydroxide creation. However, these oils often evaporate after a short period and typically do not provide long term protection. Hexavalent chromium was widely used to protect galvanized steel that could not have passivating oil applied, but is far less common now as it is extremely toxic.

Alloying elements of special steels The alloying constituents are generally divided unto carbide, austenite and ferrite forming elements. Furthermore, the purpose for which they are added to steel must be taken into consideration. According to its content, each alloying element imparts specific properties to steel. When several elements are present the effect may be increased, a fact which is fully utilized in modern alloying technology. There are, however, alloy compositions for which the individual elements do not exert their influence regarding a certain properties in the same direction, but rather counteract one another. The presence of alloying elements merely creates a prerequisite for desired properties, but it is the processing and heat treatment operations which permit us to achieve them. The principal effects of alloying constituents and trace elements upon steels will be outlined below. Aluminum-AlAluminum is the strongest and most common used deoxidizing and dentriding agent. It has therefor a favorable effect on the intensivity to ageing and it promotes a fine grain formation, when added in small amounts.As aluminium combines with nitrogen to form very hard carbides, it is used as alloying constituent in most nitriding steels.It increases the resistance to scailing and is therefore often added to ferritic heat resisting steels. In unalloyed carbon steels altizing (diffusion of aluminium into the surface) improves the scailing resistance. Aluminium narrows greatly the gamma-range. Owing to its ability to increase the coercive force, Al is used as alloying constituent in irin-nickel-cobalt-aluminium permanent magnet alloys. Antimony-SbAntimony has a detrimental effect in steel. It reduces considerably the toughness properties and narrows the gammy-range Arsenic-AsArsenic, too, narrows the gamma-range and has detrimental effects in steel because it shows a strong tendency towards segregations, similar to phosporus. The elimination of segregations by homogenizing is, however, even more difficult than in case of phosporus. Besides, it increases temper brittlenes, reduces considerably toughnes  and effects weldability. Beryllium-BeBeryllium narrows substantially the gamma-range. The addition of Be my cause precipitation hardening, entailing, however, a decline in toughness. It has a strong deoxidizing effect and a great sulphur-affinity: it has so far a very seldom been used in steels. Boron-BAs boron has a large neutron absorption cross-section, it is usually added to steels intended for the manufacture of controllers and screens for nuclear power plants. In austenitic 18/8CrNi steels, the addition of boron raises their strength and yield point through precipitation hardening, while at the same time it lowers corrosion resistance. Precipitations caused by boron improve mechanical properties of austenitic creep resisting steels at elevated temperatures. In constructional steels, this element improves through-hardening and thus entails on increase in the core strength of case-hardening steels. A reduction of weldability is to be expected in boron alloyed steels. Calcium-CaCalcium is used together with Si in the form of silico-calcium for deoxidation. It increases the scaling resistance of heating conductor materials. Carbon-CCarbon is inseparable from steel and is therefore usually not defined as alloying constituent. Carbon is the most important element for the majority of steels and has the strongest influence on their properties. In unalloyed and alloyed steels, properties can vary within a wide range by choosing different carbon contents (from a few hundredths to two percent) and a suitable heat treatment. Strength and hardenability increase with increasing C content, while elongation values forming properties, weldability and machinability are reduced. Cerium-CeIt is usually used together with lanthanum, neodymium, praseodymium and other rare earth metals as "mischmetal". It has a cleaning effect, because it is a strong deoxidizer and it promotes desulphurization. In highly alloyed steel, it has a favourable influence on the hot forming properties, andin heat resisting steels it enhances scaling resistance. Fe-Ce alloys containing approx. 70% Ce are pyrophorous (spark metals). Cerium is also used as addition to spheroidal graphite castiron. Chromium-CrChromium makes steel oil and air hardenable. By lowering the critical cooling rate necessary for the formation of martensite, it increases hardenability and thus improves heat treating properties while at the same time it reduces impact strength. Chromium is a strong carbide former. Its carbides increase edge-holding property and wear resistance. High-temperature strength and resistance to high-pressure hydrogen are improved by the addition of chromium. The resistance to scale formation increases with increasing Cr contents, while a minimum content of approx. 1 3% Cr dissolved in the matrix is required for making steel resistant to corrosion. Chromium narrows the gamma-range and thus extends the ferrite field. However, it stabilizes austenite in austenitic CrNi steels. Thermal conductivity and electric conductivity as well as thermal expansion (glass sealing alloys)are reduced by chromium. In amounts of up to 3%, chromium-combined with elevated carbon contents-increases remanence and coercive force. Cobalt-CoCobalt does not form carbides. It inhibits grain growth at elevated temperatures and improves substantially retention of hardness and high-temperature strength. It is therefor often used as alloying constituent in high-speed steels, hot-work tool steels, high-temperature and creep resisting materials. This element promotes the formation of graphite. When present in large amounts, it enhances remanence, coercive force and thermal conductivity and therefore serves as base element for high-grade permanent magnet steels and alloys. When exposed to neutron radiation, it forms the highly radioactive 60 Co isotope. For this reason, Co is an undesirable element in steels intended for use in nuclear reactors. Copper-CuCopper is only added to a few steel grades, because it builds up below the oxide layer and produces high surface sensitivity in hot forming operations due to penetration into the grain boundary. It is therefore sometimes considered to be detrimental to steels. Yield point and ratio of yield point to tensile strength are increased by copper. Cu contents above 0.3.0% may cause precipitation hardening. Hardenability is improved. In unalloyed and low-alloy steels, a marked improvement in resistance to weathering is achieved by the addition of Cu. in acid resisting high-alloy steels, Cu content above 1% increases the resistance to hydrochloric and sulphuric acids Hydrogen-HHydrogen is considered to have detrimental effects in steels. It produces brittleness due to a decline in elongation and reduction of area, without increasing the yield point and tensile strength. It causes the dreaded flake formation and promotes the formation of ghost lines. Active hydrogen produced during pickling penetrates into the steel and forms blowholes. Humid hydrogen causes decarburization at elevated temperatures. Lead-PhLead is added in amounts of 0.2 to 0.5% to free-cutting steels because its very fine suspens dispersion (lead is undissolvable in steel) permits to obtain short chip lengths and clean cut surfaces and thus it guarantees improved machinability. Lead contents within the range indicated above have practicaly no influence on the mechanical properties Magnesium-MgMagnesium promotes graphite formation in cast iron. Manganese-MnManganese has a deoxidizing effect. It combines with sulphur to form manganese sulphides and hus lowers the untavourable effect of iron sulphides. This is of particular importance for free- cuting steels because itreduces the risk of red shortness. The Ar3 and Art points are lowered; Mn reduces substantially the critical cooling rate and thus increases hardenability Yield point and strength are increased by the addition of Mn. Mn contents greater than 4% lead to a britte martensitic structure, even at a slow cooling rate, so that the alloy range is hardy utilized. Steels containing more than 1 2% Mn in combination with elevated carbon contents are austenitic because Mn enlarges considerably the gamma-range. Such steelis experience severe strain hardening of surface, when exposed to impact stresses, while the core remains tough. They are therefore highly wear resistant in case of impact stresses. Steels with Mn co tents greater than 1 8% remain non-magnetizable, even after relatively heavy cold forming, and are used as specialty steels and as steels intended for low-temperature service. Mn increases the coefficient of thermal expansion, while it reduces thermal conductivity and electric conductivity. Molybdenum-MoMolybdenum is mostly added together with other alloying elements. By reducing the critical cooling rate, it improves hardenability Mn reduces to a large extent temper brittleness, e.g. in CrNi and Mn steels, and promotes fine-grain formation. It increases yield point and strength. Being a strong carbide former, it improves the cutting efficiency of high speed steels. Mo belongs to those elements which increase resistance to corrosion and is therefore often used as alloying constituent in highly alloyed Cr steels and austenitic CrNi steels. Elevated Mo contents lower susceptibility to pitting. Mo narrows substantially the gamma-range, increases high- temperature strength and reduces resistance to scale formation. Nickel-NiIn constructional steels, Ni causes an increase of impact strength, even at subzero temperatures is therefore added to case-hardening steels, heat treatable steels and steels intended for low temperature service to increase theirtoughness properties All transformation points (A1-A4) are lowered by nickel. It does not form carbides enlarging substantially the gamma-range, Ni-in amounts of more than 7%-imparts an austenitic structure to chemically resistant high-chromium steels down to far below room temperature. Ni as single alloying element, oven in large percentages, merely slows down corrosion processes. In austenitic CrNi steels, however, it induces resistance to the attack cf reducing chemicals; the resistance of these steels in oxidizing substances is achieved by the addition of Cr. Austenitio steels show elevated strength at temperatures above 600 °C owing to their high recrystallization temperature, they are practically not magnetizable.Thermal conductivity and electric conductivity are reduced considerably. High Ni contents within precisely defined analysis limits result in steels with special physical properties, e.g. low thermal expansion (Invar grades). Nobium-Nb (columbium-Cb) and tantalum-TaThese elements occur nearly almost in combination and are very difficult to seperate from one another, so that they are usually used together. They are strong carbide-forming elements and are therefor, added as stabilizers to chemically resistant steels. Both elements form ferrite and thus reduce the gamma-range. Owing to its ability to increase high-temperature strengh and creep rupture strengh, Nb is often added to creep resisting austenitic boiler steels. Ta has a large neutron absorption cross-section; for nuclear reactor steels, only Nb poor in Ta is used. Nitrogen-NNitrogen may occur both as element having detrimental effects and as alloying constituent. It is considered detrimental because it reduces toughness as a result of precipitation processes causes susceptibility to ageing and blue brittleness (deformation in the range of blue temper heat 300-350 C) and involves the risk of initiating intergranular stress corrosion cracking in unalloyed and low-alloy steels. As alloying constituent, nitrogen enlarges the gamma-range and stabilizes the austenitic structure. In austenitic steels, it increases the strength, particularly the yield strength, and improves mechanical properties at elevated temperatures. By causing the formation of nitrides, it allows us to obtain high surface hardness (nitriding). Oxygen-OOxygen has adverse effects in steels. Its specific influence depends largely on the type and composition of its compounds in steels as well as on their shape and distribution. The mechanical properties, especially impact strength, are lowered, particularly those in transverse direction, while the susceptibility to ageing brittleness, red shortness, fibrous fracture and flaky fracture is increased. Phosphorus-PPhosphorus is considered to be detrimental to steels, because it causes heavy primary segregation during solidification and involves the risk of secondary segregation in the solid state by substantial reduction of the gamma-range. Owing to the relatively low diffusion rate in both the gamma- and alpha-solid solution Crystal phases segregations if any, are very difficult to compensale for. As it is hardly possible to obtain homogeneous distribution of phosphorus, its contents should be kept to a minimum. The extent of segregation cannot be determined with sufficient cortainty P increases susceptibility to temper brittieness, even in smallest percentages brittleness due to phosphorus gets higher with increasing carbon content, increasing Temperature, increasing grain size and decreasing ratio of reduction by forging It manifests itself Cold shoriness and sensitivity to impact stresses (susceptibility to britte fracture), In low-alloy onstructional steels with C contents of approx O 1%, phosphorus causes an increase in strength and resistance to atmosphere corrosion. Cu promotes corrosion resistance (steels with low susceptibility to corrosion, In austenitic CrNi steols, P additions may cause a yield point increase and produce precipitation effects. Selenium – SeSelenium is added to free-cutting steels where its effects are similar to those of sulphur. It is, however, more effective in improving machinability. In corrosion resisting steels, it effects corrosion resistance properties less severly than sulphur. Silicon – SiSilicon has a deoxidizing effect. It promotes graphite precipitation and narrows subtantially the gamma-range. It increases strength and wear resistance (heat treatable Si-Mn steels). Silicon causes a considerable increase of the elastic limit and is therefore most suitable as alloying constituent in spring steels. Owing to its ability to improve substantially the resistance to scaling, Si is added to heat resisting steels. Its contents are, however, limited, as it impairs the hot and cold forming properties. With a content of 12% Si resistance to the attack of acids is attained, but such steel grades are only available as very hard and brittle castings which can be only be machined by grinding.Owing to the considerable reduction of electric conductivity, coercive force and power losses brought about by silicon, this element is used in steel for electric quality sheets. Sulphur – SAmong all trace elements, sulphur produces the most serious segregations. Iron sulphide leads to red shortness because the low melting sulphide eutectics surround the grains like a net, resulting in a low coherence of the latter and in breaking up of grain boundaries during hot forming. This phenomenon is intensified by the effect of oxygen.As sulphur has an extremely great affinity to manganese, it is combined with manganese to from Mn sulphide  which is, among the usually existing inclusions, the most harmless one, being distributed point-like in steel and having a high melting point.The  toughness properties in transverse direction are substantially reduced by sulphur. S is added to free-cutting steels, as its lubrication effect on the cutting edge reduces the friction between workpiece and tool, thus permitting to obtain a prolonged tool life. Moreover, short chips are obtained in machining operations. S increases susceptibility cracks. Tellurium – TeTellurium influences steel properties in a similar manner as selenium. Contens up to 0,2% improve machinability. Tin – SnTin is detrimental to steels. Like cooper, it builds up bellow the oxide layer, penetrates into the grain boundaries and produces cracks and solder brittleness. Sn exhibits a strong segregation tendency and narrows the gamma –range. Titanium – TiOwing to its great affinity to oxygen, sulphur and carbon, titanium is strongly deoxidizing, denitriding and carbide forming and combines with sulphur.In corrosion resisting steel, it is used as carbide former for stabilization to ensure resistance to intergranular corrosion. Besides, titanium has a grain refining effect and narrows substantially the gamma-range.In higher amounts, it leads to precipitation and because of the high coercive forces obtained, it is added to permanent magnet alloys. Titanium increases creep rupture strength by the formation of special nitrides.Titanium, however, exhibits a strong segregation and banding tendency. Tungsten – WTungsten is strong carbide former (its carbides are very hard) and it narrows the gamma-range. It improves toughness and inhibits grain growth. It increases high-temperature strength and retention of hardness as well as wear resistance at elevated temperatures (red heat) and thus cutting efficiency. It is therefore predominantly added to high-speed steels, hot work tool steels, high-temperature steels and steels featuring maximum hardness. Tungsten increases considerably the coercive force and is therefore used as alloying constituent in permanent magnet alloys. It impairs the scaling resistance. Its high specific gravity becomes particularly noticeable in high-tungsten high-speed steels and hot work steels. Vanadium-VVanadium refines the primary grain and thus the as cast structure. It is a strong carbide forming element, thus causing an increase in wear resistance, edge holding properly and high-temperature strength. It is therefore a preferred alloying constituent in high-speed steels, hot work tool steels and high-temperature steels. It improves considerably the retention of hardness and reduces overheating  sensitivity. As vanadium refines the grain and inhibits air hardening by the formation of carbides, it has a favorable influence on the welding properties of heat treatable steels. Due to carbide formation, it increases resistance to high-pressure hydrogen. Vanadium narrows the gamma range and shifts the Curie point to higher temperatures. Zirconium-ZrZirconium is a carbide forming element and is used metalurgically as deoxidizing, denitrding and desulphurating agent because it leaves only a few deoxidation products. Zr additions to fully killed sulphur-containing free-cutting have a favorable influence on sulphide formation and prevention of red shortness. By forming special nitrides, it improves high-temperature strength and creep repture strengh in high temperature steels and alloys. It increases the service life of heating conductor materials and causes narrowing of the gamma-range.

WHAT IS A FERROUS METAL?There are many different categories into which metals can be placed. Some metals may be ductile, some may be brittle. Other metals could be magnetic, and some have no magnetism at all. Some types of alloys can be precipitation hardened, and others cannot. The aforementioned are important distinctions; however, when categorizing metals, one of the most important differences worth noting is whether the metal in question is ferrous or non-ferrous. What is a Ferrous Metal?A metal with the descriptor “ferrous” means that it has iron in its composition. When the term ferrous metal is used, it also usually implies that iron is a large percentage of the elemental composition. If it’s not the most abundant element, it would probably be the second or third most prolific. If a metal only contains trace amounts of iron, as many metals do, then that small amount is not considered enough to declare the metal ferrous. What are the Common Properties of Ferrous Metals?It is difficult to assign common properties to ferrous metals, since they can have a wide variety of alloying elements that greatly change their characteristics. For instance, many ferrous metals are magnetic; however, it is not true for all ferrous metals. Austenitic stainless steel, while considered a ferrous metal, is not magnetic because the large amount of nickel allows it to have a crystal structure that is predominantly austenite at room temperature. Austenite is not magnetic, although it does contain iron. Some ferrous metals, such as cast iron, are extremely strong and brittle. However, low carbon steel, another type of ferrous metal, can be quite soft and ductile because it does not contain as high of an amount of carbon as cast iron. While it is difficult to place the properties of all ferrous materials under one umbrella, there are some generalizations that can be made with some accuracy. Ferrous metals often have relatively high amounts of strength, especially when compared with copper, tin, and lead alloys. Ferrous metals are also generally hard, and if they’re not alloyed with many other elements or coated, can be subject to rust. Most ferrous materials, with the exception of austenitic stainless steel and some other grades, are magnetic. Examples of Ferrous MetalsAs was mentioned earlier in the article, there are many different types of ferrous metals. The following are some examples of ferrous metals: Carbon SteelStainless SteelCast IronAlloy SteelCarbon SteelCarbon steels are possibly the most widely used type of ferrous metal. They are primarily made up of iron, with over 90% of their chemical composition being that element. The only other major alloying element in carbon steel is carbon. There are only trace amounts of other elements. Common applications of carbon steels include structures, furniture, and automotive components. Stainless SteelStainless steel is another group of ferrous metals that are commonly used. In general, stainless steels have a high amount of chromium that helps them to resist corrosion better than carbon steels. Stainless steels can be further broken down into subgroups. Austenitic stainless steels have the most corrosion resistance, with high amounts of nickel and chromium. There are also ferritic, martensitic, and duplex stainless steels. Each has their own advantages and disadvantages depending on the application. Common applications of stainless steels include appliances, pharmaceutical and medical equipment, food-grade equipment, and knives. Cast IronCast iron is a type of ferrous metal that has more carbon than most other types. This gives it a high amount of strength. Although high in strength, it is quite brittle. The lack of other alloying elements outside of iron and carbon make it a relatively affordable ferrous metal. Common applications of cast iron include cookware, small components subject to wear such as gears, rods, and pins, and mining equipment. Alloy SteelAlloy steels are a type of ferrous metal specially formulated to serve specific purposes. While composed primarily of iron, differing amounts of copper, vanadium, tungsten, manganese, and other elements can be used to tailor an alloy steel to have higher toughness, ductility, tensile strength, hardness, and other properties. Common applications of alloy steels include tools, dies, and machining equipment.

IS STAINLESS STEEL MAGNETIC?If you ask someone “is stainless steel magnetic?” you will likely get a variety of responses. Some people believe that stainless steel is a completely non-magnetic material. Others believe that stainless steel must be magnetic because it contains iron. However, like with most things, the answer lies somewhere in between. The fact is, some types of stainless steels are magnetic while others are not. What Makes a Stainless Steel Magnetic?In order for stainless steel to be magnetic, a couple of requirements need to be met: The stainless steel must have iron in itThe stainless steel must have its crystal structure be arranged in a ferritic or martensitic structure.First and foremost, since stainless steels are a type of steel, which means they must contain iron in their chemical composition. That takes care of the first requirement. The second requirement is that the stainless steel must have its crystal structure be arranged in a ferrite or martensite structure. If a stainless steel is mostly comprised of an austenite structure, then it will not be magnetic. Which Types of Stainless Steel Are Magnetic?Magnetic and non-magnetic stainless steels can typically be grouped together based on the type of stainless steel. The following types of stainless steel are typically magnetic: Ferritic Stainless Steels such as grades 409, 430 and 439Martensitic Stainless Steel such as grades 410, 420, 440Duplex Stainless Steel such as grade 2205Ferritic Stainless Steels:Ferritic stainless steels are typically magnetic as they have large quantities of ferrite in their chemical composition. Ferrite is a compound of iron and other elements. The combination of a ferritic crystal structure with iron makes ferritic stainless steels magnetic. However, some ferritic stainless steels may have a weaker magnetic pull than normal carbon steel. Martensitic Stainless Steels:Many martensitic stainless steels are magnetic. The unique crystal structure of martensitic steels can be ferromagnetic if iron is present. Since stainless steel is a type of steel, there is an abundant amount of iron in its make-up. This makes many martensitic stainless steels magnetic. Duplex stainless steels:Duplex stainless steels are typically magnetic because they contain a mixture of austenite and ferrite. The substantial amount of ferrite (which is magnetic) contributes to Duplex steels being magnetic. However, since duplex stainless steels have more austenite than ferritic steels, they may be slightly less magnetic. Austenitic Stainless Steel:Austenitic stainless steels have a high amount of austenite which makes them mostly non-magnetic. Even though grades such as 304 and 316 stainless steel have high amounts of iron in their chemical composition, austenite means they are non-ferromagnetic. However, if the crystal structure of an austenitic stainless steel is changed through work-hardening or special thermal treatment, then ferrite can form in some locations making the steel partially magnetic. Why Does It Matter?Magnetic material can have a huge effect on the intended performance of a material depending on its application. If a material needs to be quickly sorted from other materials, then having one material be magnetic can make this a very easy sorting process to carry out. When welding or performing other metal fabrication processes, magnetic material may cause issues to arise. Electrical currents can also behave differently in magnetic materials.