Quote Originally Posted by sharpshooter
Yes...what the print says verbatim:
heat treat, Cn R15N 89 MIN, case depth .012-.015"
Cn means carbo-nitride,(case harden). The "R15N 89 MIN" has me perplexed. It has something to do with hardness, but the only methods I am familiar with is Rockwell A,B,C scales, Brinell and Shore hardness. Is there another measurement of hardness I have overlooked?
Not that I am aware of, I have some guys on another forum that are metallurgists, maybe they would know.