Just curious where the guys doing heat treat on their own stainless with sub zero treatment are getting their stuff. I haven't had much luck tracking down dry ice anywhere to use in a slurry. Way back when I worked at a grocery store in high school, we got blocks in every day in frozen shipments, but they say they don't get any shipped in anymore. Additionally, I would probably have to buy a dewar to purchase liquid nitrogen, but I'm not sure where one would purchase nitrogen. Do you need some type of permit or can anyone but the stuff? Thanks guys.
Gas supply companies like Parxair, normally sell dry ice and I would think they could help with the liquid nitrogen.
