The general guiding principle of mold non-standard parts processing is to adapt to different materials, different shapes and different technical requirements. It has certain plasticity and can achieve good processing effect by controlling the processing.

According to the shape and shape of the parts, the parts can be divided into three categories: shafts, plates and shaped parts. The common process is roughly: roughing--heat treatment (quenching, quenching and tempering)--finishing--electric Processing - fitter (surface treatment) - assembly processing.

Heat treatment of parts

The heat treatment process of the parts requires the internal stress to be controlled while ensuring the required hardness of the parts, and to ensure the dimensional stability of the parts during processing. Different materials have different treatment methods. With the development of the mold industry in recent years, the types of materials used have increased. In addition to Cr12, 40Cr, Cr12MoV, and hard alloys, some new materials, such as convex and concave molds, with strong working strength and strong stress, can be used. Such as V10, ASP23, etc., such materials have high thermal stability and good tissue state.

For parts made of Cr12MoV, quenching is performed after roughing. After quenching, the workpiece has a large residual stress, which may lead to finishing or cracking during work. After quenching, the parts should be quenched and tempered to eliminate quenching stress. The quenching temperature is controlled at 900-1020 ° C, then cooled to 200-220 ° C to be air-cooled, and then quickly returned to the furnace 220 ° C tempering, this method is called a hardening process, can obtain higher strength and wear resistance, for wear The mold that is the main failure form works well. In the production, some workpieces with many corners and complicated shapes are encountered. The tempering is not enough to eliminate the quenching stress. Before the finishing, stress relief annealing or multiple aging treatment is needed to fully release the stress.

For powder alloy steel parts such as V10 and APS23, because they can withstand high temperature tempering, quenching can be performed by secondary hardening process, quenching at 1050-1080 °C, and then tempering at 490-520 °C for several times. High impact toughness and stability are suitable for molds where chipping is the main failure mode. Powder alloy steel has a high cost, but its performance is good, and it is forming a wide application trend.