In order to improve the performance of the material when processing precision parts, improve the cutting performance of the material and eliminate the internal stress of the workpiece, some heat treatment procedures should be properly arranged during the processing. The arrangement of the heat treatment process in the process route mainly depends on the material of the part and the purpose of the heat treatment.
Pay attention to the scheduling time of the process when performing the heat treatment process.
- Prepare for heat treatment. The purpose of the preliminary heat treatment is to improve the cutting performance of the material, eliminate the residual stress during the manufacturing of the blank, and improve the structure. The process position is mostly before processing, and methods such as annealing and normalizing are commonly used.
(Heat treatment of knife edge)
2. Eliminate residual stress. Since the internal stress generated during the manufacturing and processing of the blank will cause deformation of the workpiece and affect the processing quality, heat treatment must be arranged to eliminate residual stress. The best arrangement of heat treatment to eliminate residual stress is after rough machining and before finishing. For parts that do not require high precision, artificial aging and annealing are usually carried out before the blank enters the processing workshop to eliminate residual stress. For complex castings with high-precision requirements, two aging treatments are usually arranged during the machining process: casting-rough machining-aging-semi-finishing-aging-finishing. For high-precision parts, such as precision screws, precision spindles, etc., multiple heat treatments should be arranged to eliminate residual stress, and even ice-cold treatment is often used to stabilize dimensions.
(Precision machining parts)
3. Final treatment. The purpose of the final treatment is to improve the strength, surface hardness and wear resistance of the parts, and it is usually carried out before the machining (grinding) of the precision parts. Commonly used are quenching, carburizing, nitriding and carbonitriding. Therefore, in the process of machining mechanical parts, in order to improve the mechanical properties of mechanical parts, it is necessary to perform heat treatment processing procedures on the parts, so as to ensure that the processing quality meets the needs of product use.