There are many heat treatment processes for wear-resistant composite plates, and they are applicable to different ranges, such as direct quenching and low-temperature tempering, which cannot refine the grains of steel, the workpiece has large quenching deformation, and the surface residue of the carburized parts of the wear-resistant composite plate The amount of austenite is large and the surface hardness is low. Simple operation and low cost. It is used to deal with parts that are not deformed and bears little impact load. It is suitable for gas carburizing and liquid carburizing processes.
The wear-resistant composite plate is pre-cooled and directly quenched and tempered at low temperature. The quenching temperature is 800-850℃, which can reduce the quenching deformation of the workpiece. The amount of retained austenite in the infiltrated layer can also be slightly reduced. The surface hardness of the surfacing wear-resistant composite plate is slightly Improved, but the austenite grains did not change. Widely used in various tools made of fine-grained steel.
The secondary quenching and cold treatment of the wear-resistant composite board is mainly used for high-alloy steel workpieces that are not mechanically processed after carburization. Carburizing high temperature tempering, one-time heating quenching, low temperature tempering, quenching temperature 840-860℃, mainly used for Cr-Ni alloy carburized workpieces.
The countermeasures for the wear-resistant composite board are secondary quenching and low-temperature tempering, mainly to improve the structure of the infiltrated layer. When the core performance is not high, it can be quenched between Ac1-Ac3 of the material, and when the core performance is high, it should be quenched above Ac3. It is mainly used for important carburized parts that require high mechanical properties, especially for coarse-grained steel. However, after carburizing, high temperature heating is required twice, which increases the deformation of the workpiece and increases the oxidative decarburization, and the heat treatment process is more complicated.
The wear-resistant composite plate is quenched by heating at one time, tempered at low temperature, and the quenching temperature is 820-850℃ or 780-810℃; for those with higher core strength, use 820-850℃ quenching, the core is low carbon M, and the surface hardness is required. For higher ones, quenching at 780-810℃ can refine the grains. Suitable for solid carburized carbon steel and low-alloy surfacing wear-resistant composite plate workpieces, gas and liquid carburized coarse-grained steel.
