Wondering what is different about this M4 bladed Para 2, and the 52100 bladed Para 2?
Both have carbon fiber scales and a type of "tool" steel, yet there is a $45 price difference?
What am I missing?
52100 has approx 1% carbon and just a bit of chromium ( 1.30-1.60 ). I find it sharpens up pretty quickly and holds a decent working edge, but is prone to rust and pitting if it is not dried and maintained after use. M4 has more carbon...1.4%....and hence has excellent wear resistance and good toughness . As well, M4 has
slightly more chromium ( about 4%), and while that is not nearly enough to give it any stainless properties, it seems to be enough to make for a blade that will stain, spot and turn grey, but not form rust as quickly as 52100. You can't leave it sitting in a wet sink overnight, however.
But to get to the heart of your question, 52100 is a ball bearing steel, and if I'm not mistaken I think Latrobe/Carpenter and Niagara all produce it. The M4 used by Spyderco is Crucible's CPM (Crucible Particle Metallurgy) process. M4 is a versatile high-speed steel with higher carbon and vanadium contents for exceptional abrasion-resistance. It is well suited for premium cutting tools of all types, particularly those used for machining abrasive alloys, castings and heat-treated materials. The high carbon content enables M4 steel to be hardened to a higher HRC. However, the high hardness and high vanadium carbide content make it more difficult to grind after heat treatment compared to 52100. Although CMP-M4 provides enhanced machinability and grindabiltiy over standard M4, as I understand it.
PLEASE, those who have more knowledge correct me, where I have erred. I do not want to be be spreading mis-information!
https://www.spyderco.com/forumII/viewtopic.php?t=71542