汽车传动轴热处理工艺强化要求确定研究

Research on Determination of Strengthening Requirements of Heat Treatment Process of Automobile Transmission Shaft

针对当前轴类零部件热处理强化要求确定及工艺设计过程中,仅考虑机械零件的最高应力和热处理工艺本身,无法确定热处理强化层深度、强度及硬度梯度分布等强化要求。基于此,以材料为25CrMo4的某轿车等速万向传动轴为研究对象,通过对传动轴进行应力分析,并结合强度-应力干涉模型确定强度分布要求,基于材料-加工-产品强度-热处理工艺,确定最终的热处理方式为“渗碳+淬火+低温回火”。工艺强化要求芯部硬度不小于480 HV,表面硬度不小于630 HV,渗碳层深度为0.5~1.0 mm。研究结果可为工程中的热处理工艺强化要求的确定奠定理论基础。

In the current process of determining heat treatment strengthening requirements for shaft parts and process design,only the highest stress of mechanical parts and the heat treatment process itself can not determine the strengthening requirements such as the depth of heat treatment strengthening layer,strength and hardness gradient distribution.Based on this,this paper takes a constant speed universal transmission shaft of a car whose material is 25CrMo4 as the research object.Through stress analysis of the transmission shaft,combined with the strength-stress interference model,the strength distribution requirements are determined.Then,based on the material-processing-product strength-heat treatment process,the final heat treatment method is determined as“carburizing+quenching+low temperature tempering”.Process strengthening requirements for core hardness of not less than 480 HV,surface hardness of not less than 630 HV,carburizing layer depth of 0.5~1.0 mm.This study provides a theoretical basis for the determination of heat treatment process strengthening requirements in engineering.