Common Knowledge in the Heat Treatment Industry

　　Heat treatment furnaces, classified by process, include heating furnaces as well as furnaces for annealing, tempering, quenching, and more. Classified by furnace type, they include carriage-type heating furnaces, through-type furnaces, chamber-type forging furnaces, and others.

　　What is heat treatment?

　　A process method in which solid metals or alloys are heated and held at a suitable temperature for a specified period of time, then cooled at a controlled rate to alter their microstructure and thereby achieve the desired properties.

　　What is the purpose of heat treatment?

　　By modifying the internal microstructure of steel through appropriate heat treatment processes, it is possible to control the extent of microstructural transformation and the morphology of the resulting phases during phase transitions, thereby enhancing the steel's performance.

　　What are the conditions for heat treatment?

　　1. The three basic processes of heat treatment are: heating, holding (at temperature), and cooling.

　　2. Conditions for heat treatment: (1) Involves solid-state phase transformation; (2) Alloys whose solubility changes significantly upon heating.

　　3. Heat treatment can only alter the matrix microstructure of cast iron; it cannot change the morphology of the graphite.

　　4. Similarly, solid-phase transformations during the cooling process require undercooling.