What Is 420 Steel
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- Oct 8,2022
What Is 420 Steel?
The 420 steel is part of the 400 series of steels that’s very popular due to their very friendly prices. The 420 steel has been around for a long time, and its particular combination of low price with adequate performance will most likely keep it popular for many years to come.
The 420 steel is popular for many types of uses, particularly because despite the low price it is hard enough for use in knives. In addition, it qualifies as stainless steel, so it doesn’t rust very easily.
Common Uses of 420 steel
The 420 steel is actually kind of versatile, since plenty of manufacturers find the adequate hardness and good corrosion resistance useful for many types of consumer items. These items include:
· Budget pocket knives
· Low-end hunting knives
· Butterfly knives (balisong knives)
· Cutlery (including steak knives and other types of table knives
· Scissors
· Shear blades
· Surgical instruments
· Needle valves
· Various hand tools
420 Steel Chemical Composition
Let’s check out the specific alloys used for 420 steel, and the amounts for each alloy. Each alloy will have a particular effect on the steel, depending on the amount.
· Carbon, 0.15% at the most
· Manganese, 1.00% at the most
· Chromium, 12% to 14%
· Silicon, 1.00% at the most
· Phosphorus, 0.04% at the most
· Sulfur, 0.03% at the most
Carbon, 0.15% at the most: The carbon content is the principal element for determining the hardness of the resulting steel. As you can see, there’s really not much carbon here.
But the 420 steel can be treated properly that it can still be useful for knives. The carbon here also helps with the hardenability of the steel, meaning that the 420 steel responds nicely to proper heat treatment.
Manganese, 1.00% at the most: Many consider manganese as next in importance only to carbon. At this amount, it helps with boosting the strength of the steel. It also improves the surface quality of the steel.
Chromium, 12% to 14%: With this amount of chromium, the 420 steel qualifies as stainless steel (or at least, lower-end stainless steel). The chromium is instrumental in boosting the corrosion resistance of the steel. In addition, chromium can improve the yield strength of the steel, as well as its hardenability.
Silicon, 1.00% at the most: The silicon acts as one of the main removers of oxygen bubbles in the molten steel. The silicon also strengthens the steel when the silicon dissolves in the iron content.
Phosphorus, 0.04% at the most: That’s a tiny amount of phosphorus, because in general the phosphorus is considered an impurity. Even a little bit can make the steel brittle. But when limited to such a tiny amount as this, it’s actually helpful. It boosts the strength of the steel, and even helps with corrosion resistance. It also makes the 420 steel more machinable.
Sulfur, 0.03% at the most: This is another impurity at higher amounts, but here it helps with machinability. You just don’t want more than this tiny amount, as that can reduce the toughness and ductility of the steel.
420 Steel Hardness
The hardness of 420 steel will depend on how the manufacturer treats the steel before it’s available for purchase. In 420 knives, however, the hardness can reach at least 50 HRC.
That’s basically good enough hardness for knives, but just barely. That’s why 420 steel knives aren’t meant for heavy duty. These knives aren’t hard enough compared to just about al the other knife steels out there, so edge retention is a problem. But at least its relative softness makes it easier to sharpen.
Does 420 steel rust?
Well, it can rust but not all that easily. In fact, if you take good care of the knife and wipe it dry regularly, then it will take a long time for corrosion to be an issue.
That’s because there’s enough chromium here for 420 steel to qualify as stainless steel. It nicely resists corrosion that can be caused by fresh water, air, foods, alkalis, and mild acids.
Of course, you should avoid using this in a seawater environment. And its best to minimize its use on unwashed food substances, as that can lead to pitting corrosion.
Properties of 420 steel
Extremely Affordable
This is perhaps the most distinguishing feature of 420 steel. A 420 steel knife is definitely a budget option, so it’s great when you’re buying dinner knives in a set.
Easy Sharpening
While the edge retention for 420 steel knives isn’t great (it’s nearer to lousy, to be honest), at least it doesn’t take much to sharpen an edge. Any sharpening tool can do the job with much time and effort needed.
Good Corrosion Resistance
This has enough chromium to qualify as stainless steel, though just barely. You should still wipe the steel blade dry after each use, and you don’t want to use this in saltwater. But it won’t have any problem with regular fresh water and even food acids.
Versatile
This can be used in a wide variety of knives. It works for ED and outdoor knives, as well as dinner knives.
420 Equivalent Steels or Alternative
Another effective way of realizing the true worth of 420 steel is to compare it directly with other steels with somewhat similar attributes. Here’s how the 420 steel does in relation with some other steels.
420 vs 440 stainless steel
Both these steels are part of the 400 steel series, and they’re both known for their carbon and chromium content.
But the 440 steel contains a lot more carbon, ranging from 0.60% to 0.75% carbon. That makes the 440 steel better at wear resistance and edge retention. The resulting steel is definitely harder in the 440. The 440 steel also contains more chromium, so it’s even more corrosion-resistant. But the steel is more expensive than 420 steel.
420 vs 430 stainless steel
The 430 steel is much different than the 420, as the 430 contains several other alloying elements not found in 420 steel. While the 420 steel offers excellent corrosion resistance, the 430 is even better at resisting corrosion.
But the 430 steel doesn’t really work for knives, since it doesn’t harden through heat treatment. You may find the 430 steel used for butter knives, but not for any other type of knife that cuts materials harder than butter.
420 vs 316 stainless steel
The 316 is a very common type of steel used for stainless steel tools for surgical and food applications. It’s also an extremely corrosion-resistant steel, as it can even perform well against saltwater. But it doesn’t contain a lot of carbon, so you basically never find this steel used for knives. You can’t use heat treatment for 316 steel.
420 steel vs 1095
The 1095 can be found in some knives, and like 420 steel it’s very affordable. It offers decent edge retention and good toughness. However, it’s not nearly as corrosion resistant as 420 steel, because 1095 steel doesn’t qualify as stainless steel.