In nickel alloys and austenitic stainless steels, where chromium is added for corrosion resistance, the mechanism involved is precipitation of chromium carbide at the grain boundaries, resulting in the formation of chromium-depleted zones adjacent to the grain boundaries ( this process is called sensitization ).
22.
Knives and other cooking tools that are made of carbon steel, semi-stainless steels like D2 or specialized, highly hardened cutlery steels like ZDP189 should also not be placed into a dishwasher, as these steels are not corrosion resistant or far less corrosion resistant than the austenitic stainless steels used for cookware.
