Research and Application of 20Cr2Ni4A Material for Transmission Output Shaft
In order to meet the development requirements of high torque transmissions,the carburized gear steel 20Cr2Ni4A material was applied to the transmission output shaft parts.The process route of air cool-ing after carburization,followed by high-temperature tempering and secondary quenching were used to ef-fectively control the residual austenite content on the surface of 20Cr2Ni4A material,while causing the precipitation of dispersed carbides on the surface of carburized layer.In addition,two different carburizing heat treatment processes were developed to verify the effects on the hardness of parts at the surface and 3/4 R,as well as the static torsional strength of output shaft parts.The results indicated that different carburizing heat treatment processes only affected the effective hardening depth of parts,and increasing the effective hardening depth had little influence on the surface and core hardness and the static torsion strength.