A8-mod is a modified version of AISI A8. It’s a conventional cold work tool steel, with a medium carbon content and alloyed with chromium, molybdenum and vanadium. It exceeds most knife steels in toughness. Toughness is a property often overlooked in knife steels, often on behalf of corrosion and wear resistance. The thing is that a sharp edge with a decent edge angle (<35° total angle) needs toughness to avoid breakage of the edge/chipping, especially when working with hard materials like wood. Because of this, edge retention of this steel will be better than higher alloyed steels and even powder steels for many purposes.
Many combat and survival knives are made today in brittle steels like S30V, D2, ATS-34 and 440C. These have very little safety margin and will break without warning when overloaded. A8-mod has, even on a hardness of over 60 HRC, ductility and will bend before fracture. (This doesn’t mean that it is soft.)
All knives can be broken, knives in A8-mod will just give you a much harder time doing so.
A little more on this.
My interest in knives are primarily the technical aspect with focus on functionality and mechanical properties as toughness and wear resistance. To achieve excellence in my knives I use the optimum materials for knives available today, and I have access to heat treatment practices unavailable for most knifemakers.
My background as a metallurgist gives me an understanding of materials beyond that of most. This is a great resource in most parts of knife making, especially in material selection and heat treatment. There is a vast number of steels on the marked, and those considered the best are in most cases not. To evaluate and choose materials you have to understand how the steel is affected by the composition and heat treatment.
My background as a metallurgist gives me an understanding of materials beyond that of most. This is a great resource in most parts of knife making, especially in material selection and heat treatment. There is a vast number of steels on the marked, and those considered the best are in most cases not. To evaluate and choose materials you have to understand how the steel is affected by the composition and heat treatment.