Japanese high speed powder tool steel from Hitachi Steelworks. It is recognized by many users as the best rusty powder steel on the market. Due to the mixture of incredible amounts of carbide-forming elements, the hardness and strength of this steel are extremely high. Chrome, improving e.g. tensile strength, sharpness and corrosion resistance, molybdenum to improve machinability and strength, vanadium and tungsten to improve wear resistance and hardness, with a large addition of cobalt (which increases the positive effect of each of the above-mentioned elements) make knives made of HAP 40 reliable. The hardness achieved by this steel is unbelievable, reaching 64-68 HRC. This steel is distinguished by amazing sharpness, but due to its hardness sharpening will be a challenge. It is a steel that is partially resistant to corrosion, but it is worth paying attention to its maintenance (cleaning and oiling), as it may rust. Is this steel suitable for knives then? I think that after reading the description, you have no doubts, this steel is great for extreme cutting, you can count on its strength and hardness. However, it needs more care than typical stainless steel, but with proper care, knives made of HAP 40 steel will serve you faithfully.
Composition:
- Carbon: 1,27-1,37%,
- Chromium: 3,70-4,70%
- Molybdenum:4,60-5,40%,
- Tungsten: 5,60-6,50%
- Vanadium: 2,80-3,30%,
- Manganese: 0.50%,
- Cobalt: 7,50-8,50%,