High-speed steel high-temperature carburizing low-temperature quenching process, mold steel manufacturers to introduce you

The low-temperature quenching process of high speed steel carburized at high temperature is described in detail.

Under the carburizing condition of 930℃×8h, the surface carbon content of T1 steel reaches 2.60%, and the depth of carburizing layer with carbon content higher than 1.0% is about 0.75mm. In the carburizing process of high-speed steel, due to the large amount of carbide elements, its chemical reaction mechanism is different from that of ordinary carbon steel, which exists not only in the form of solid solution in austenite during the absorption and infiltration, but also in the form of carbide Presence, that is, in the infiltration of the same time precipitation.

In fact, most die steel welding carburizing gas is precipitated at carburizing temperature in the form of carbides, all of which are granular, and their types vary with increasing carbon content, in the order of MC → M6C → M23C6 → M3C.

The above examples show that M3C type carbides are already present in the 2%C seepage layer. Injection mold steel at a certain austenitizing temperature, solid solution carbon increases with the increase of carbon content in the steel. From the mold steel h13 range, the increase in solid solution carbon is beneficial to secondary hardening, but excessive prompting residual austenite product increases instead of reducing the secondary hardness.

Just like the effect of carbon saturation on the tissue transformation of HSS, the carburized layer has different characteristics from the core quenching, tempering and secondary hardening. If heated to the proper temperature prior to carburizing and quenched at the heart, the surface will be overheated and overburned.

Conversely, if the carburized layer is quenched to bring out the secondary hardening properties of a normal quench, then the core is in an underheated condition. In the case of too high carbon content on the surface of the carburized layer and too steep distribution gradient, the above contradiction is even more prominent, and it is difficult to find a temperature at which the dual potential of the surface and the heart can be basically played normally for die steel 4cr13.