Chen Yong, Luo Li, Zhang Yuquan, Zhou Xingyun, Zeng Deshan, Yu Fucheng
State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures, Guangxi University, Nanning 530004, China.
School of Mechanical Engineering, Guangxi University, Nanning 530004, China.
Materials (Basel). 2024 Nov 25;17(23):5764. doi: 10.3390/ma17235764.
To improve the contact fatigue life of gears, we studied the effect of adding a certain proportion of the Al element to a 20MnCr5 steel FZG spur gear under different heat treatment processes, characterizing the retained austenite and residual compressive stress on the tooth surface. The stability of the microstructure grain size on the gear surface under different heat treatment processes was studied, and the surface microstructure, phase structure, and composition of the gear were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The changes in the retained austenite content and grain size on the gear surface at a microscale of 2-100 μm were investigated. In addition, this study revealed the effect of adding the Al element and the optimization of the carburizing and quenching process on the residual compressive stress on the gear surface at a depth range of 200-280 μm. The effect of higher residual compressive stress and fewer non-metallic inclusions on the gear surface on the stress intensity factor of fatigue crack propagation was considered, along with the effect of deeper hardened layers on the improvement in wear resistance. The experiments in this study significantly improved the contact fatigue life of 20MnCr5 steel gears.
为提高齿轮的接触疲劳寿命，我们研究了在不同热处理工艺下，向20MnCr5钢FZG圆柱齿轮中添加一定比例Al元素的效果，表征了齿面上的残余奥氏体和残余压应力。研究了不同热处理工艺下齿轮表面微观组织晶粒尺寸的稳定性，并使用扫描电子显微镜（SEM）和X射线衍射（XRD）对齿轮的表面微观组织、相结构和成分进行了表征。研究了在2 - 100μm微观尺度下齿轮表面残余奥氏体含量和晶粒尺寸的变化。此外，本研究揭示了添加Al元素以及渗碳淬火工艺优化对200 - 280μm深度范围内齿轮表面残余压应力的影响。考虑了齿轮表面较高的残余压应力和较少的非金属夹杂物对疲劳裂纹扩展应力强度因子的影响，以及较深硬化层对耐磨性提高的影响。本研究中的实验显著提高了20MnCr5钢齿轮的接触疲劳寿命。
