为研究激光喷丸强化对医用Ti6Al4V合金表面耐生物腐蚀性能的影响, 对Ti6Al4V合金试样表面进行激光喷丸强化处理; 然后选用动电位极化曲线测试法研究了激光喷丸前后试样的电化学腐蚀性能, 采用扫描电子显微镜观察腐蚀试样的表面形貌并进行能谱分析。结果表明, 在测试参数范围内, 激光喷丸强化试样的自腐蚀电位正移, 腐蚀倾向降低; 钝化电流密度降低, 钝化区电位范围增大, 钝化性能更稳定; 击穿电位正移, 点蚀敏感性降低; 自腐蚀电流密度减小, 腐蚀速率降低。与未处理试样相比, 自腐蚀电位最大正移了0.209 V, 钝化电流密度最大降低了2个数量级, 钝化区电位范围最大增幅为86.90%, 击穿电位最大增幅为88.31%, 自腐蚀电流密度最大降低了81.75%。激光喷丸强化处理可有效改善医用Ti6Al4V合金表面的耐生物腐蚀性能。

In order to investigate the effect of laser peening (LP) on surface biological corrosion resistance of medical Ti6Al4V alloy, LP experiment was carried out on Ti6Al4V alloy and the electrochemical corrosion property of the alloy was investigated using potentiodynamic polarization curve method. The surface morphology of etched samples was observed by scanning electron microscope, and the energy spectra were measured. The results show that the self-corrosion potential of LP samples shifts positively and corrosion tendency decreases in the range of tested parameters; the passivation current density decreases while the potential range of passivation region increases, and passivation performance is more stable; the breakdown potential shifts positively and pitting susceptibility also decreases; the corrosion current density and corrosion rate all decrease. Compared with the untreated samples, the self-corrosion potential of LP samples maximally shifts 0.209 V and the passivation current density is reduced by two orders of magnitude; the maximum increases of the potential range of passivation region and breakdown potential are 86.90% and 88.31%, respectively, and the self-corrosion current density is maximally decreased by 81.75%. Therefore, LP process can effectively improve the biological corrosion resistance of the medical Ti6Al4V alloy.