Different grades of stainless steel respond differently to temperature changes. They would either warp or sheer apart depending on how well the two layers were

Different grades of stainless steel respond differently to temperature changes. They would either warp or sheer apart depending on how well the two layers were bonded. The same principal is how many thermometers work https://en.wikipedia.org/wiki/Bimetallic_strip https://en.wikipedia.org/wiki/Bimetallic_strip