This process generally refers to the heat treatment of a material in order to optimise its properties. The aim is to improve the strength and resistance to chemicals, to reduce the stresses in the material structure that arise, for example, through machining or quenching, and ultimately to increase the temperature resistance.
The material properties of plastics, for example, are optimised by hot storage. Depending on the material of the workpiece, tempering is carried out at temperatures below the softening range or crystalline melting range.
Suitable furnace designs are, for example, continuous furnaces or tempering furnaces. During annealing, a constant temperature and optimal air circulation should be ensured inside the furnace. To prevent heat accumulation, the workpieces should be exposed.
The process of annealing makes it possible to change the structure of the respective workpiece, such as the structure of workpieces made of cast iron or the transformation of the crystal structure of thin layers. Tempering is therefore used in the glass and plastics industries as well as in metal processing.