1. After quenching and cooling to normal temperature, the material continues to cool in the environment below 0℃, which is called cold treatment. After cold treatment, the material has high mechanical properties and stable specifications.

2. Metaphorically, after something happens, put it on hold for a while and wait for a suitable opportunity to deal with it. Cold dealing with feelings is a way to deal with contradictions between the two sides. This way avoids the secondary damage caused by the initial contradiction, and it is also a way to calm the impulsive thoughts and restore rational judgment as soon as possible.