When measuring the surface residual stresses generated by turning Ti6Al4V tube parts, considering the accuracy, convenience of the measurements and material saving, an appropriate length of the tube was chosen based on the FEM result. When the ratio of the length to the external diameter reachesλ≥50/45 =1.11, the edge effect to the accuracy of the measurements can be neglected. In order to compensate the changes of the residual stresses caused by layer removal, the FEM correction method was used to correct the stress values got by XRD method, and the results revealed that the surface residual stresses generated by turning in both cutting and normal directions were compressive, the magnitude of the residual stress in the cutting direction was larger than that in the normal direction, at the depth of 60 μm, the residual stresses in both directions reduced nearly to 0. The measuring process has revealed that the computation is simple, as proven by FEM, the accuracy of the FEM correction method is much higher than that of the traditional correction method, so it can be applied in practice.%为精确测量车削加工钛合金薄壁管件引起的表面残余应力，综合考虑测量精度、可操作性以及节约材料等因素，运用有限元法（ FEM）分析确定零件合适的轴向长度，结果表明：当管件的轴向长度与外径比值λ≥1．11时，其边缘效应对于测量结果的影响可以忽略不计．为对零件剥层后新表面应力值变化进行补偿，运用FEM修正法对X射线法测得的剥层后表面应力值进行修正，测量结果表明：Ti6Al4V管件车削加工引起的表面残余应力在轴向和切向上均呈压应力状态，切向应力高于轴向应力，深度为60μm时，两个方向的残余应力都已基本趋于0．表明该修正方法计算简单，其修正精度明显高于传统修正方法，可以广泛运用于实际表面加工残余应力的测量过程．
展开▼
