In part one of this article, I mentioned that blade steels are clearly divided into two categories consisting of non-stainless, high-carbon, tool steels and stainless steels.
I also mentioned that for knives regularly subject to impact such as camp knives, survival knives, military knives and machetes, you need to choose a tough steel rather than a hard steel. For high quality hunting knives, you need to choose a hard steel rather than a tough steel.
But, which blade steel do you choose for your particular purpose?
Well, if toughness, keenness of edge, and/or ease of resharpening are of paramount importance to you, then choose a knife made from a high carbon tool steel such as 1095, 5160, O1, or A2. The high carbon blade steels tend to be softer but has a finer grain structure with better edge performance and toughness than stainless steels.
On the other hand, if edge holding ability and corrosion resistance are most important to you, then choose a stainless blade steel such as CPM S30V, VG-10, 154CM, ATS34, or 440C.
Keep in mind stainless steels tend to have poorer edge performance and be less tough than high carbon steels.
Furthermore, for large, high-impact, knives such as Parangs, Eneps, and Kukris, a non-stainless steel such as 1055 or 65Mn is best. But for military or survival knives, one of the harder, high-carbon, tool steels such as 1095 mentioned above is best.
If you’re looking for superior edge holding ability and corrosion resistance, choose a premium stainless blade steel such S30V or VG-10. For slightly lower performance choose D2, 154CM, or ATS34 and, for large stainless steel knives such as Bowies, choose 440C.
Another factor that you’ll want to consider when choosing a blade steel is the Rockwell Hardness (Rc) of the finished blade. Hardness and toughness in a knife blade are inversely proportional.
Therefore, although the perfect blade steel would be one that is both hard and tough, no one has yet managed to formulate such an alloy. Softer blade steels (Rc 52-54) are tougher than hard blade steels (Rc 58-62) but they do not hold an edge as well.
Hard blade steels hold an edge better but are more prone to chip or break because they are more brittle.
Last, you will want to note the elemental composition of each blade steel. For instance, Carbon converts iron into steel and makes it harder whereas, Chromium increases the wear and corrosion resistance.
Molybdenum increases hardness, abrasion resistance, and corrosion resistance and Manganese is an inexpensive means of refining the grain structure, which increases toughness and hardness. Tungsten and Vanadium are better, but more expensive, ways of achieving the same goal.
So, when choosing a blade steel, it is very important that you first identify your needs and then chose an appropriate blade steel accordingly in order to obtain the best performance for your particular purpose.
Please feel free to post your suggestions and comments about this article below.