more ? about the mystery steel

[peter nap]

Ok, I took some time to examine the mystery steel that I tried to melt the other day. I am confused and need some of you heat treat experts to set me straight. The stuff turned a beautiful grey, like it had been etched. When I dumped it out I just let it sit on a fire brick until it was cold. I tried to unroll it and couldn't. I had no trouble rolling it up. I took a file and tested it. It was harder. My guess is about an R56 or 57. I took one of the unheated pieces and tried the file. Much softer just like annealed steel.

It's obvious that it air hardened. Any ideas on how to improve the hardness and how to temper it. The heated piece is suitable for a knife blade as is but there must be more to it than that. The first time had to be luck. It also has not rusted.

I know no nothing about air hardening and am open to suggestion. (please)

One other thing, it does not seem brittle??

 

[rfrink]

Peter,

Try to anneal it by water quenching a redhot sample. Check to see if it gets softer rather than harder after a redhot quench in water....that will shed some light on the metalurgical properties. Maybe a precipitaion hardening material....?

Rob