How to heat treatment for precision metal processing?

Precision hardware processing includes a part of the heat treatment method. The cognition of the heat treatment design requirements of the parts is basically based on the cognition of the changes in the use of materials and processing, so this is a very systematic knowledge structure, it is not exist in isolation.

So, what is precision metal processing heat treatment?

In view of the frequency and importance of various methods in the machining process, we choose the following types for analysis, that is, focus analysis. In the machining process, we use more than four heat treatment methods: annealing, normalizing, quenching and tempering.

01 Annealing treatment

The definition of annealing treatment: a metal heat treatment process in which a metal part is heated to a certain high temperature, kept for a period of time, and then allowed to cool naturally.

Its main function:

A. Reduce the hardness of the parts and improve the machining performance;

B. Eliminate the residual stress of the parts, stabilize the size, and reduce the probability of deformation and cracks;

C. Refine the grains, adjust the structure, and eliminate the defects of the material structure;

D. Uniform material organization and composition, improve material properties or prepare organization for subsequent heat treatment processes

02 Normalizing treatment Definition of normalizing treatment: heat metal parts to a certain high temperature, keep it for a period of time, and then let it cool in the air by spraying water, spraying, blowing, etc., which is different from annealing treatment in that its The cooling rate is faster, so the resulting material has a finer structure and improved mechanical properties.

Its main function:

A. Remove the internal stress of the material;

B. Reduce the hardness of the material and improve the plasticity;

03 Quenching treatment Definition of quenching treatment: Heat the metal parts to a temperature above the critical temperature Ac3 or Ac1, keep it for a period of time, make it fully or partially austenitized, and then quickly cool to below Ms at a cooling rate greater than the critical cooling rate Heat treatment process for martensitic transformation.

Its main function:

A. Greatly improve the rigidity, hardness, wear resistance and fatigue strength of precision hardware parts;

B. Meet the physical and chemical properties of some special steels such as ferromagnetism and corrosion resistance.

04 Tempering Treatment Definition of tempering treatment: refers to a process in which the quenched and hardened or normalized steel is immersed at a temperature lower than the critical temperature for a period of time, and then cooled down at a certain speed to increase the toughness of the material. a heat treatment method.

Its main function:

A. Eliminate the residual stress generated when the workpiece is quenched to prevent deformation and cracking;

B. Adjust the hardness, strength, plasticity and toughness of the workpiece to achieve better performance requirements;

C. Stable organization and size to ensure accuracy;

D. Improve and improve processing performance.