On 2018-08-08 14:48:54
Introduction of heat treatment process
Heat treatment processing is, the first to carry out a reasonable selection of materials, take the mold as an example, for the density of complex mold to choose good quality micro-deformation abrasive steel; Forging and tempering heat treatment are carried out for the abrasive steel with severe carbide segregation, and the double refining heat treatment is carried out for the larger or unforged abrasive steel.
Secondly, the design of the mold should be reasonable, symmetrical shape; For the larger mold to master the law of deformation, reserved processing margin; Large and sophisticated moulds can be constructed in combination; Pre-heat treatment is also required. Of course, reasonable selection of heating temperature and temperature control for heat treatment processing is also very important, can be used to slow heating, preheating and other balanced heating methods to reduce the mold heat treatment deformation.
If conditions permit, vacuum heating and quenching and cryogenic heat treatment after quenching should be adopted as far as possible. In addition, proper operation of heat treatment process and reasonable tempering heat treatment process are also limited measures to reduce the deformation of precision and complex mold.
Second simple understand, heat treatment process is heating, heat preservation and cooling process, is an important part of the machinery industry, modern manufacturing chain indispensable important link, is to promote metal material potential into full play, improve the inherent quality and the service life of the key mechanical parts processing process, is the foundation of manufacturing technology.
For example, quenching is a heat treatment process of heating steel to a temperature above the critical temperature of Ac3 or Ac1, holding it for a period of time, making it austenitized in whole or in part, and then cooling it to below Ms at a cooling rate faster than the critical cooling rate for martensite transformation. Tempering is a heat treatment process in which the quenched workpiece is heated to a suitable temperature below the critical point AC1 for a certain period of time, and then cooled in a suitable manner to obtain the desired microstructure and properties.
In heat treatment, normalizing is the heat treatment process of pearlitic structure obtained by heating steel or steel parts to the critical point, keeping the appropriate temperature above AC3 or ACM for a certain time and then cooling in the air. Annealing a heat treatment process in which the subeutectoid steel workpiece is heated to 20-40 degrees above AC3 and then cooled in the air with the furnace slowly cooled to below 500 degrees after holding for a period of time. In addition, there are many, including spheroidization annealing, solution heat treatment, aging, tempering heat treatment.