I spent about an hour, out of curiosity, trying to come up with a number but couldn't find one specific to ANZA. I did get bits and pieces of info that might help.
1. Modern files are made out of air hardening steels, which means they can't be forged.
2. Common modern files run an Rc of 62-64 and are quite brittle, something I learned on my own.
3. The couple of references I saw to knives made out of modern files list an Rc of around 58; which is quite good. 440C and S-30V for instance use that same hardness(known as optimal hardness).
4. The actual manufacture is a bit of a puzzle though, since I found two conflicting bits of info:
A. One Anza advertisement I looked at says the files are annealed(which doesn't make sense), cold ground(you cold grind hardened steel to keep the hardness....if it's annealed it doesn't matter how you grind it, since it needs to be re-heat treated), and tempered(that made sense).
B. At another forum an individual said he looked at an Anza video where they say that the the files are simply cold ground and tempered...which makes perfect sense.
I started out making knives out of old Sandvik and Nicholson files and did them as in B(cold ground and re-tempered). I was hopefully getting an Rc between 58-60 when I re-tempered them. I mostly gave them away or sold them cheap and folks were really impressed with them. An Rc of 58 is a good compromise between hardness and toughness, and is actually a lot better than what many factory carbon blades are...a friend with a Rockwell tester tested a popular carbon German made blade and the Rc was 45; which is barely spring temper.
Conclusion: Based on their reputation for edge holding, I'm willing to bet that 58 is the number they're using. Not sure whether the exact process is worth worrying about, as long as the final product works...I just get curious
. Still can't understand why they don't publish the number though. Considering the prices I've seen you'd expect excellent workmanship.
