How to choose the materials for stamping molds?

　　In stamping molds,various metal and non-metallic materials are used,mainly including carbon steel,alloy steel,cast iron,cast steel,hard alloy,low melting point alloy,zinc based alloy,aluminum bronze,synthetic resin,polyurethane rubber,plastic,laminated birch board,etc.The materials used for manufacturing molds are required to have high hardness,high strength,high wear resistance,appropriate toughness,high hardenability,no deformation(or less deformation)during heat treatment,and no cracking during quenching.

　　Reasonably selecting mold materials and implementing the correct heat treatment process are the key to ensuring the lifespan of the mold.For molds with different uses,comprehensive considerations should be made based on their working state,stress conditions,and the properties of the processed materials,production batch size,and productivity,with a focus on the various performance requirements mentioned above.Then,corresponding choices should be made for steel grades and heat treatment processes.

　　When the production batch of stamping parts is large,the materials for the working parts of the mold,including the convex and concave molds,should be selected from high-quality and wear-resistant mold steel.The material of other process structure parts and auxiliary structure parts of the mold should also be correspondingly improved.When the batch size is not large,the requirements for material performance should be appropriately relaxed to reduce costs.

　　When the material being stamped is harder or has greater deformation resistance,the convex and concave molds of the stamping die should be made of materials with good wear resistance and high strength.When drawing stainless steel,aluminum bronze concave molds can be used because they have good adhesion resistance.The guide pillar guide sleeve requires wear resistance and good toughness,so low-carbon steel surface carburization and quenching are often used.For another example,the main disadvantage of carbon Tool steel is its poor hardenability.When the section size of the stamping die part is large,its central hardness is still low after quenching.However,when working on a press with a large number of strokes,its good impact resistance becomes an advantage.For parts such as fixed plates and discharge plates,not only should they have sufficient strength,but they also require minimal deformation during operation.In addition,cold treatment,cryogenic treatment,vacuum treatment,and surface strengthening methods can also be used to improve the performance of mold parts.For cold extrusion molds with poor working conditions for convex and concave molds,mold steel with sufficient hardness,strength,toughness,wear resistance,and other comprehensive mechanical properties should be selected,and at the same time,it should have a certain degree of red hardness and thermal fatigue strength.

　　The cold and hot workability of materials and the existing conditions of the factory shall be considered.Pay attention to using micro deformation mold steel to reduce machining costs.For molds with special requirements,it is necessary to develop and apply mold steel with specialized performance.The selection of mold materials should be determined based on the usage conditions of the mold parts,ensuring that low-cost materials are selected to reduce costs while meeting the main conditions.