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为了提高车轴疲劳强度,本文基于超声挤压强化技术,研究了其对列车专用30CrMoA车轴钢加工表面的影响.对比分析了超声挤压强化前后工件表面外观、表面粗糙度、残余应力等特征的变化,绘制了残余压应力沿层深分布的曲线.结果表明:超声强化后的试件表面达到了很好的镜面效果,表面光滑且具有光泽,消除了前道工序残留的环状纹路;表面粗糙度得到改善,粗糙度数值由原来的3.746μm降低到0.2μm左右,在前道工序的基础上下降了95%左右;原来的残余拉应力可以被调节成为压应力,残余压应力层的深度可以达到近2mm,阻止了疲劳裂纹的萌生和扩展,有利于提高金属材料的疲劳强度和使用寿命.
In order to improve the fatigue strength of the axle, this paper studies the effect of ultrasonic squeeze strengthening technology on the machined surface of 30CrMoA axle steel for trains, and analyzes the changes of surface appearance, surface roughness and residual stress before and after the squeeze hardening , The curve of the distribution of residual compressive stress along the layer depth is drawn.The results show that the surface of the sample after ultrasonic hardening achieves a good mirror surface with a smooth and shiny surface and eliminates the annular grooves remaining in the previous process; The roughness value is reduced from 3.746μm to 0.2μm, which is about 95% lower than that of the previous procedure; the original residual tensile stress can be adjusted to be compressive stress, the depth of residual compressive stress layer can be Reached nearly 2mm, to prevent the initiation and expansion of fatigue cracks, is conducive to improving the fatigue strength of metal materials and service life.