What should be paid attention to in the processing and manufacturing of plastic molds


1. Forging process. This is an important link in the ma […]

1. Forging process. This is an important link in the manufacturing process of plastic mold working parts. For the plastic mold of high alloy tool steel, technical requirements are usually put forward for the metallographic structure such as the carbide distribution of the material. In addition, the forging temperature range should be strictly controlled, the correct heating specification should be formulated, the correct forging force method should be adopted, and the forging should be cooled slowly or annealed in time.
2. Preparatory heat treatment. Depending on the material and requirements of the working parts of the plastic mold, preliminary heat treatment processes such as annealing, normalizing or quenching and tempering should be used to improve the structure, eliminate the organizational defects of the forging blank, and improve the processing technology. After proper preparatory heat treatment, high carbon alloy die steel can eliminate reticulated secondary cementite or chain carbide, make carbide spheroidized and refined, and promote the uniformity of carbide distribution. This is conducive to ensuring the quality of quenching and tempering and improving the life of the mold.
3. Quenching and tempering. This is the key link in the heat treatment of the mold. If overheating occurs during quenching and heating, it will not only cause greater brittleness of the workpiece, but also easily cause deformation and cracking during cooling, which will seriously affect the life of the mold. When the die is quenched and heated, special attention should be paid to preventing oxidation and decarburization, and the heat treatment process specification should be strictly controlled. When conditions permit, vacuum heat treatment can be used. After quenching, it should be tempered in time, and different tempering processes should be adopted according to technical requirements. plastic mold
4. Stress relief annealing. After the plastic mold is processed, the stress relief annealing treatment should be carried out. The purpose is to eliminate the internal stress caused by rough machining, so as to avoid excessive deformation and cracks caused by quenching. For molds with high precision requirements, stress relief tempering is required after grinding or electrical machining, which is conducive to stabilizing mold accuracy and improving service life.