Cold Steel uses this type of three layer sandwich steel construction in some of its blades. I have read about what the company puts out on this and the idea of a harder center for the cutting edge and softer steel for the back and two sides of the blade for flexibility. I have had someone try to explain it further to me once. But, I guess I am just not understanding and do not have the engineering concepts to appreciate this type of steel.

I collect Boker Damascus Steel knives, as well, and think I have a real understanding of the purpose of the varied steel layers in Damascus blades. I have and have read the definitive book on the subject by Manfred Sachse and refer back to it from time to time.

I am aware of the arguments about temperature and merging of steels but the idea that an outer layer of flexible steel gives flexibility to the entire blade, I just don't get it. The outer layer may protect the harder inner layer but that is the only benefit I can see other than the aesthetic one of potential for a prettier blade.

Anyone interested in discussing this subject with the intent of educating me, would be greatly appreciated.