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.

Vanadis 4 Extra

I have been using Vanadis 4 Extra for many years now. It’s a high alloyed non-stainless powder metallurgical steel not to different from a high speed steel, except it is optimized for cold work instead of hot cutting of metal. It has a high content of vanadium giving small, evenly distributed vanadium carbides. Vanadis 4 is one of the toughest powder steels available, and thereby one of the best powder steels suited for knife application. In stainless and higher alloyed powder steels the chromium and other carbide forming elements lead to a very high volume fraction carbides. This reduces toughness (also for powder steels), and in a knife blade this brittleness will lead to wear of the edge by chipping and carbide tear out, and reduced edge retention. Vanadis 4 has a good balance between hardness, wear resistance and toughness where edge retention is the primary goal.
I heat treat this steel up to 66 HRC depending on the use. With more advanced steel, one also need to be more precise in the heat treatment and should have good knowledge about metallurgy before attempting working with them.
Here is an article on this from Knivprat.