Knife Steel Types Explained
Stainless, powder metallurgy, tool, high-speed and carbon knife steels explained: what defines each type and which steels belong to it.
Knife steels fall into a handful of families. Two questions separate them: does the steel have enough free chromium to resist rust, and is it cast as an ingot or made from powder?
Ingot vs powder metallurgy
Conventional steel is melted and cast into ingots. As a highly alloyed ingot cools, its carbides grow large and cluster, which makes the blade brittle and hard to grind. Powder metallurgy (PM) atomises the molten alloy into fine powder and consolidates it under heat and pressure, so carbides stay small and evenly spread. PM is what makes steels such as S30V, M390 and MagnaCut practical for knives.
Stainless steels
Conventional (ingot) stainless steels with enough free chromium, roughly 12% or more, to resist rust in everyday use.
On SteelChart: 14C28N, 154CM, 420HC, 440C, 8Cr13MoV, AEB-L, AUS-8, LC200N, N690, Nitro-V, VG-10. Average ratings: edge 3.5, toughness 6, corrosion 7.2, sharpening 7.6 (out of 10).
Powder metallurgy stainless steels
Stainless steels made by powder metallurgy, which keeps carbides small and evenly spread so high-alloy steels stay tough enough for knives.
On SteelChart: 20CV, CTS-XHP, Elmax, M390, MagnaCut, S30V, S35VN, S45VN, S90V, SG2 (R2), ZDP-189. Average ratings: edge 7.2, toughness 4.4, corrosion 7.5, sharpening 3.8 (out of 10).
Tool steels
Ingot tool steels designed for dies and cutting tools; high wear resistance, limited corrosion resistance.
On SteelChart: D2. Average ratings: edge 6, toughness 3, corrosion 4, sharpening 4 (out of 10).
Powder metallurgy tool steels
Powder metallurgy tool steels that combine high toughness with wear resistance, with little corrosion resistance.
On SteelChart: CPM 3V, CruWear. Average ratings: edge 6, toughness 8, corrosion 3, sharpening 5.5 (out of 10).
High-speed powder steels
Powder metallurgy high-speed steels with tungsten, molybdenum and vanadium; very high hardness and edge retention, low corrosion resistance.
On SteelChart: CPM M4, HAP40. Average ratings: edge 8, toughness 4.5, corrosion 2, sharpening 3 (out of 10).
Carbon steels
Simple carbon and low-alloy steels: easy to sharpen and often tough, but they rust and patina without care.
On SteelChart: 1095, 80CrV2, Shirogami #2. Average ratings: edge 3.3, toughness 6.3, corrosion 1, sharpening 9.3 (out of 10).
See how the families spread out on the steel chart's edge retention vs toughness plot.
Ratings are relative 1-10 scores at typical knife hardness; see the methodology. Updated 2026-10-14.