As heat treatment is a complex process, its concept is not easy to describe. There are many metal processing procedures used for metal shape processing or making metal surface bright and clean - such as rolling, forming, machining and electroplating - but only the use of medium frequency induction heating equipment for heat treatment can greatly change the z-end properties of metal materials.
Grinding can sharpen the blade, but heat treatment can maintain high hardness and strength.
Forging and machining can process a crankshaft, but heat treatment can improve the strength of the crankshaft and make the journal more wear-resistant.
The coil spring can be produced by stamping. Only heat treatment can make it have high elasticity.
So, the question is, what is heat treatment?
Generally speaking, heat treatment is a process to control the heating and cooling time and temperature of metal, so as to make the expected crystal structure change inside the metal. In addition to metals, other materials, such as plastics, glass and ceramics, can also be heat treated with medium frequency induction heating equipment.
If the word "internal" is omitted, the meaning of heat treatment can be literally understood to include welding, flame cutting and even smelting. However, in the traditional metallurgical theory, heat treatment is related to the atomic structure and the improvement of the atomic structure. The use of medium frequency induction heating equipment for heat treatment almost does not involve external physical property changes. At the same time, it is only applicable to solid metal, never used for liquid metal.
However, not all metals and their alloys that can be softened by heat treatment with medium frequency induction heating equipment can be hardened by heat treatment. Heat treatment is often mistaken for a quenching and hardening process and is often mistaken for heat hardened metals only. Metals can be heat treated and hardened after alloying, but not only alloys can be heat treated and hardened.
Although there are many types of heat treatment, the annealing process is mainly used to soften metals. Annealing is often carried out after cold working such as forging, cutting and bending, which changes the physical properties of metal materials. Cold working mechanically changes the crystal structure of materials, resulting in hardening of materials. As a simple example, bending paper clips or staples repeatedly will make them hard and brittle until they break.
Proper heat treatment (such as annealing) can make the metal recrystallized after work hardening, so that the metal becomes softer, more ductile and more suitable for subsequent cutting.