AISI D2 Cold Work Tool Steel Application Analysis

What is too steel?

Tool steel is a type of carbon alloy steel that is well-matched for tool manufacturing, such as hand tools or machine dies. Its hardness, resistance to abrasion and ability to retain shape at increased temperatures are the key properties of this material. Tool steel is typically used in a heat treated condition which provides increased hardness.

Types of Tool Steel. The different tool steel grades include:

Water Hardening

Air Hardening

Cold Work tool steel

Hot work tool steel

Oil Hardening

Shock resisting types

What is cold work tool steel?

The cold-work tool steels include the O series (oil-hardening), the A series (air-hardening), and the D series (high carbon-chromium). These are steels used to cut or form materials that are at low temperatures. This group possesses high hardenability and wear resistance, and average toughness and heat softening resistance. They are used in production of larger parts or parts that require minimal distortion during hardening. The use of oil quenching and air-hardening helps reduce distortion, avoiding the higher stresses caused by the quicker water quenching. More alloying elements are used in these steels, as compared to the water-hardening class. These alloys increase the steels' hardenability, and thus require a less severe quenching process and as a result are less likely to crack. They have high surface hardness and are often used to make knife blades. The machinability of the oil hardening grades is high but for the high carbon-chromium types is low.

What is D2 steel?

D2 steel is a high carbon – high chromium air hardening cold work tool steel, heat treatable to 60-62 HRC. D2 offers excellent wear and abrasion resistance, due to large volumes of carbides in the micro-structure. D2 steel is widely used in long production cold work applications requiring very high wear resistance and high compression strength. It is machinable in the annealed condition, and, like other air hardening tool steels, exhibits minimal distortion in heat treat. D2 steel is available in de-carb free rounds, flats, and squares, as well as ground flat stock and drill rod.

What D2 steel used?

Typical applications for D2 steel are blanking, forming, and trim dies, gages, slitting cutters, wear parts, lamination dies, thread rolling dies, drawing dies, rotary cutting dies, knurls, bending dies, gages, shear blades, burnishing tools, rolls, machine parts, master parts, injection screw and tip components, seaming rolls, extrusion dies, tire shredders, scrap choppers, Stamping dies, Forming Dies, Punches, Forming Rolls, Knives, slitters, shear blades, Tools, Scrap choppers, Tyre shredders, etc.

Why choose D2?

D2 steel will retain its hardness up to a temperature of 425 °C (797 °F). The chromium-rich alloy carbides in the D2 steel create excellent resistance to wear from sliding contact with other metal or abrasive materials. This steel has a high wear resistance and creates a tough knife that holds an edge. The essence of D2 steel is high-carbon high-chromium cold-working die steel. The advantage of high-carbon steel is that it can easily reach high hardness after heat treatment and has good wear resistance. The disadvantage is that it is easy to form carbide aggregation. It is resulting in extremely high local hardness.

D2 steel applications

A popular grade for toolmakers,this tool steel is used in a wide variety of tool making applications.Typical applications include punching and blanking dies for stainless steel sheet,brass,copper,zinc and hard abrasive materials generally.Other application suitable for this tool steel include deep drawing dies,cupping dies,forming dies,sheet metal forming rolls,shear blades for strip and sheet including flying shears,circular cutters for cold rolled strip,trimmer dies,thread rolling dies,cold extrusion dies,broaches,plug gauges,ring gauges,master hobs for cold hobbing plastic moulds, cut moulds for plastics,special taps, straybolt taps,brick and tile mould liners.

The field of application is in drawing and bending tools, plastic molds in the processing of abrasive polymers, machine knives, cold shear knives, cold extrusion tools, thread rolling dies, thread rolling rolls, thermoforming tools, cutting and punching tools and milling cutters. As a high-performance cutting steel, it can also be use in high-performance cutting tools such as dies and punches

D2 steel character

high-alloy steel for through-hardening with moderate machinability; extremely wear resistant and low warpage, good dimensional stability, toughness and through hardenability

Cool work tool steel

Cool Work oil steel

High wear resistance

Good hardenability with hardness obtained at 58-62 HRC and being hardened by NITRIDING resulting in hard surface

Used to cast coining molds, forming molds, paper cutting knives, rolling mills

Chrome-molybdenum-vanadium steel with big hardenability for hardening in oil and in air, especially high resistance to the wear (higher than by 1.2080), good cutting power, very good firmness in the pressure, lower toughness (but higher than by 1.2080). This steel shows good dimensional stability at the heat treatment, suitable for hardening to the secondary hardness (the possibility of nitriding). Further the steel is very difficult to sharpen, it works at the heat with difficulties and has a rather difficult workability in the annealed state.

D2 Steel Suitability

Tools for cold cutting, i.e. all kinds of tools with the long durability for cutting on presses and punching of materials of smaller thicknesses and materials of high hardness (especially difficult-shape tools for cutting, e.g. transformer metal sheets and metal sheets from stainless steels), knives for plate shears for the sheet and strip steel up to thickness of 10 mm of sheared material, knives for wire cutting etc. Tools for mechanical working such as e.g. smaller girders and tools for drawing, all kinds of tools for transformation and punching of materials. Further the steel is suitable for simple and symmetric tools for pressing and pushing, tools for thread rolling, plain and profile rolls, swages and also for cold work. Cutting tools such as broaching thorns, profile knives and difficult-shape milling machines for lower cutting speeds and for treatment of nonmetallic abrasive materials. Further the steel is applied in the production of highly stressed molds and their components for working of plastic and powder substances, glass, porcelain and ceramic materials. By tools for crushing and grinding it is used for hammers of crushers and jaws for mild grinding and crushing.