Sanait Mould Co., Ltd All Rights Reserved
Sanait Mould Co., Ltd
Add.: ChangPing Town, Dongguan City, GuangDong Province,China
Zip Code: 523000
Anyone wishing produced molds can be used longer, save unnecessary expenses, while the application process can be Practice makes perfect, improve the quality of mold, extending the life of the heat treatment will be carried out, it will be in the process heating What impact?
Effect of heating rate: mold deformation after heat treatment is generally thought to be caused by cooling, which is incorrect. Mold is correct or not tend to produce especially complex mold , processing of the mold deformation greater impact , compared to some of the mold heating process is evident , heating speed, often have a greater deformation.
(1) Modification reason: any metal when heated to be expanded, since the steel when heated, within the same mold, the temperature of each part of the uniform( ie, uneven heating )is bound to result in inconsistent expansion of the various parts of the mold, thereby forming internal stress due to uneven heating. In the following phase transition temperature steel, uneven heating main thermal stress, uneven heating than the phase transition temperature, will produce unequal organization transformation, both produce organizational stress. Therefore faster heating, temperature of the mold surface and the central portion of the difference between the larger, the greater the stress, deformation of the mold heat treatment is greater.
(2) preventive measures: for complex mold should be heated in the following phase transition point is slowly heated, in general, mold vacuum heat treatment deformation is much smaller than the salt bath furnace heating quenching. Preheating, low-alloy steel mold can be used for a warm-up (550-620oC; for high alloy steel mold should be preheated secondary (550-620oC and 800-850oC).