steels and oxidation

[Raudt89]

Hello, I have been researching a bit about steels, but I have not been able to clarify the doubts I have, so I will ask here and in other groups, forgive me if you find the same publication in several of them.
As I have read, not all the steels used to make knives are stainless, so:
-How are they protected from rust? Any heat treatment? I know there is bluing, but I am referring to the case of the natural silver color. Or am I missing something?
-Do the firearms receive any treatment to avoid said rust?
-What steel do knife manufacturers use for folding handles? Stainless?

I have seen mild steel recommendations for engraving, but can this mild steel be used for making knife handles?

My latest works have been developed in 316 stainless steel that I understand is one of the worst, frankly I have never engraved on other steel.
All these concerns are due to I have a 2mm thick plate that I am almost sure is mild steel, I have tried engraving on it and it is literally a sweetheart. Now I see the difference compared to 316, which is very doughy. It would be great if I could use this sheet steel for my next projects, but I am concerned about rust. Do you have anything that can help me? Thanks in advance.

 

[707chrisa]

Hi there hundreds of alloys used for guns and knifes. You are asking about Fe alloys I believe ? Almost any alloy with Fe in it will rust given enough time and through in some heat and salt even so called stainless will show discoloration and yes without getting too lost in the weeds there some rely good stainless alloys. I wish I knew what Ruger uses in there guns I have shot mine in the rain put them back into wet salt ridden leather holsters and they wipe clean the next day ( don't do this at home I am a professional gun slob.) Yes 316 sucks and cuts like old hard bubble gum its hard to forge and yes there are people who can forge works of art out of stainless not me I don't like the stuff that much to learn all the tricks to it. If you do find some magic spray that will keep steel in the white please please let me know. I have tried silicone sprays all kinds of clear coats . Bluing it just controlled rusting . This is one of the biggest bains of metal working keeping stuff from rusting. There are many Knife supply online stores with lots of info on stainless used for all types of knifes. If the jobs worth doing get the right stuff , stainless is not gold get the right alloy for what you need its not that expensive. Ps I still make knifes out of old springs but I don't sell them and I don't cry when I find a cold shut crack in them. I am just having fun doing something cheep .