DIYbanter - View Single Post - Is our view of old engineering distorted by the products which survive?

Christopher Tidy

wrote:
On Sep 22, 2:10 pm, "Ed Huntress" wrote:

Eh, eh. ...well, sonny...let's see here, by cracky...scratch, scratch,
spit...

Stainless kitchen cutlery from the 50s -- even the expensive stuff. It was
made of 18-8 (300 Series) steel, which is too soft to hold an edge. Poor
choice, or availability, of materials.

Ed Huntress

If I recall correctly Robelson found that cryogenic treatment of
stainless improved the hardness and edge holding. I just can not
remember when, but think it was in the 50's. So that might have been
400 series stainless before the heat treatment was refined.

Is that essentially quenching starting at room temperature?

Best wishes,

Chris