Ice tempering is a process that is only beneficial on stainless steel shears. Ice tempering is used to freeze the steel in order to prevent premature dulling of the cutting edges. This dulling occurs due to the high content of chromium in the steel. In order to harden steel, it must be heated to temperatures higher than 2000°F. To combat a prematurely dulled edge, the steel is then subjected to temperatures between -50°F and -60°F.