Ti-6Al-4V合金表面超声振动滚压强化研究

采用超声振动滚压加工技术对Ti-6Al-4V合金表面进行处理,探究该项技术对Ti-6Al-4V合金表面质量的影响。通过对该工艺加工前后的Ti-6Al-4V合金进行表面粗糙度参数、XRD图谱、截面微观形貌、表层残余应力及显微硬度的对比分析,结果表明:经该工艺处理后的合金表面各项粗糙度参数皆有明显降低;加工后的合金表面XRD图谱的衍射峰减弱且宽化,衍射角向高角度方向偏移;加工后的合金表层β相组织相较加工前明显细化,且随着深度增加β相组织逐渐增大;在距离表面约50μm位置的残余应力值最大可达到-967 MPa;加工后的合金表面显微硬度可达到421HV,且在0~140μm的深度范围内,显微硬度随着深度的增加逐渐减小至与基体硬度一致。经超声振动滚压加工后的Ti-6Al-4V合金表面质量显著提高,有利于提高其零部件的使用性能。

Research on ultrasonic vibration rolling strengthening of Ti-6Al-4V alloy surface

Ultrasonic vibration rolling technology was used to treat the surface of Ti-6Al-4V alloy to explore its effect on the surface quality of Ti-6Al-4V alloy.Comparative analysis of the surface roughness,XRD pattern,cross-sectional morphology,surface residual stress and micro-hardness of Ti-6Al-4V alloy before and after processing was performed.The results show that after the treatment,the roughness parameters of the alloy surface are significantly reduced,the diffraction peaks of the XRD pattern are weakened and widened,and the diffraction angle shifts toward higher angle.Theβ-phase structure of the alloy surface after the treatment is significantly refined compared with that before processing,and theβ-phase gradually becomes larger with increasing the depth.The residual stress value at a position~50μm away from the surface can reach a maximum of-967 MPa.The microhardness of the processed alloy surface can reach 421 HV.With the depth ranging 0~140μm,the microhardness gradually decreases as the depth increases,consistent with the hardness of the matrix.The surface quality of Ti-6Al-4V alloy after ultrasonic vibration rolling is significantly improved,which is beneficial to improve the performance of its parts.