Melting and Solidification (Freezing)

Abstract

Melting and solidification are the two phenomena that frequently occur in nature and in many technological processes. Good examples of the phenomena that occur in nature are ice melting and water freezing, ground freezing (the uppermost surface layer), solidification of vulcanic lava and the melting processes that evolve deep under the earth surface. Examples of the phenomena that occur in many technological processes are the freezing and thawing of food products, casting, production of plastic products, welding, electrolytic machining and thermal energy accumulators, which make use of the metal or wax melting or freezing phenomena. In the cases when pure metals, ice or eutectic alloys undergo a phase change, one can observe a clear cut line between a liquid and a solid and a definite melting point t _m .