Does a carbon steel knife stay sharper longer than a stainless steel knife?

Answer 1

AnswerCarbon steel knives are generally easier to sharpen, but more susceptible to corrosion.

Even simple steels with higher carbon content, e.g. AISI 1095 can be hardened to much higher levels compared to mainstream stainless alloys, at those levels stainless steel becomes too brittle. Edge holding, especially on soft materials is better at high hardness, i.e. carbon steel will have the advantage.

Obviously, exotic stainless PM alloys like ZDP-189 or Cowry-X are exception, but in general, average stainless steel used knives can't be hardened as high.

For the same reason(lack of toughness), stainless steel is almost never a good choice for large knives. It either has to be too soft to have enough toughness, or compromise its strength to have better edge holding ability.

Edge holding of the stainless steel might be better compared to simple carbon steel alloys at lower hardness, due to Chromium Carbides in stainless steels, but carbon, or non-stainless steels with other alloying elements such as Vanadium, Tungsten, Niobium(Columbium) have much harder carbides than Chromium forms. Their edge holding is a lot better compared to most of the stainless steels.

E.g. tool steels M2, M4, Japanese cutlery steels Aogami 1, Aogami II, Aogami Super, Shirogami 1, 2, 3, they are all "carbon steels" by definition, yet very few high alloy stainless steels can keep up with them.

Additional information about knife steels in the links section.

I've heard that looking at the polish on steel can tell you whether or not it's carbon or stainless. Stainless steel contains chromium which would make the polished steel very reflective while carbon would look dull by comparison. This argument doesn't involve things like brushed stainless though and would only really work in person.

Answer 2

Despite what many says..stainless can be used to make swords, but they have to be very carefully heat treated as full hardness would break too easily. Generally though..I would say non stainless alloys would be the better option as they are usually more resistent to breakage then stainless steels are.

Answer 3

Both can be practical choices depending on the specific type of steel you choose and the heat treatment. For example; stainless can be used, but it has to be heat treated to a slightly softer Rc hardness then you normally would as you wouldn't want the edge to chip or the sword to break. With that being said, I would choose the tougher stainless steels though such as Ats34, or Cpm s30v over something like 440c.

It would also depend on the type of sword as certain swords require a bit flexibility in which case carbon steels would be better. With proper heat treatment, you can't go wrong with stainless though. Improper heat treatment from factories have just presented a bad image for stainless swords.

Answer 4

That is a common misconception;largely due to the improper heat treatment of factory-mades. It depends entirely on the specific steel types and their heat treatment.

For example; a 1090 (basic high carbon) knife would have better edge retention then a 303 stainless steel knife, as 303 isn't suitable for blade material. However; for stainless steels that are suitable (Such as 440c, Ats34, etc), tests indicate that they actually hold a edge better then high carbon.

Answer 5

it's depends on application of manufacturing for example

1) if material is used sliding or rolling over each other then hard material is required like for gears cast iron is better than metal seel

2) if manufacturing used for hi tensile load then black steels good

Answer 6

A carbon steel sword will rust more readily.

Answer 7

1095 high carbon steel