Decalescence

The temperatures at which decalescence occurs vary with the amount of carbon in the steel, and are also higher for high-speed steel than for ordinary crucible steel.

The decalescence point indicates the temperature at which a decided change In the Internal condition of steel takes place, and above which steel must be heated in order that it may be properly hardened by quenching.

A very important feature is that steel containing hardening carbon, i.e., steel above the temperature of decalescence, is non-magnetic.