Heat treatment is a process to improve the performance of metal materials and their products. According to different purposes, the material and its workpieces are heated to a suitable temperature, kept warm, and then cool by different methods to change their internal organization to obtain the required performance. Through heat treatment, the use of efficiency or life of steel can be improved, and in some cases, cheaper general metal materials can replace more expensive special materials.
The basic methods of heat treatment are:
1. Annealing
Annealing is a process in which the steel pipe is heated to a slightly higher or lower critical temperature, kept for some time (ie, heat preservation), and then slowly cool.
2. Normalizing
Normalizing, also known as “normalization”, is to heat the steel to a temperature of 40~60℃ or higher above the upper critical point (Ac3 or Acm) to achieve complete austenitization and homogenization of the structure, and then release it, and The process of uniform cool about natural circulating air.
3. Quenching
Quenching is a process that heats steel to a suitable temperature, keeps it warm, and then rapidly cools it (usually cooling in water, oil, or air) to transform supercooled austenite into martensite. Generally used to increase the hardness and strength of parts, or change their physical and chemical properties (such as conductivity, magnetism, corrosion resistance, etc.).
4. Tempering
Tempering is a heat treatment process in which the quenched steel parts are heated to a temperature below the critical point Ac1 and then cool to room temperature after heat preservation. It is a process that must be performed after the steel is quenched, and it is also the last process of heat treatment.
Post time: Dec-05-2023