超声波法检测轨道车辆残余应力时,由于被检测部位的表面附着物、表面粗糙度、表面弧度的差异会造成检测结果出现很大误差,这对有效评判被检测部位的残余应力峰值及分布会产生很大影响.基于上述考虑,以轨道车辆常用的A7N01铝合金为研究对象,从表面附着物、表面粗糙度、表面弧度3个方面系统研究表面耦合状态对残余应力检测误差的影响.结果表明:表面存在圆弧过渡时,应采用修正后的圆弧探头;使用砂纸对喷砂面适度打磨,可以提高超声法应力测试精度,但过度打磨会破坏喷砂层或者形成新的附加机械应力层,对测试结果产生明显影响;超声法可对涂装油漆件直接进行应力测试,油漆层对t0影响极其明显,但K值与第一临界入射角影响不大,所以必须修正t0大小.%The surface radian,surface roughness and surface adhesive materials will affect the detection errors of residual stress of the components when the vehicles were under ultrasonic wave residual stress detection,then the detection results will affect the residual stress distribution and peak value greatly.This paper is focused on the research of the effect of surface radian,surface roughness and surface adhesive materials of A7N01 aluminum alloys.The results showed that the arc probes should be adopted when the surface was in the circular arc transition.The abrasive papers should be used to polish the sandblasted surface and it would promote the detection precision but the detection results would be affected if the surface was in excessive polished and formed additive stress layer and destroyed the surface.The painting coating could be detection directly and the painting layer did not affect the first critical incident angle greatly but affect the t0 greatly.So the t0 must be amended.
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