Influence of laser shock peening parameters on the abrasive wear behavior of TC4 titanium alloy under controlled cycling impact

The effects of laser shock peening (LSP) parameters (laser shock times and laser energy) on the impact abrasive wear behavior of TC4 titanium alloy were studied under the sand environment using self-developed impact wear test equipment. The mechanical properties, energy response, wear scars, and wear mechanism were analyzed. The wear scars under the sand and no-sand environments show a significant difference. The dynamic response and wear scars of the specimens vary with different laser shock times and laser energy. Under the same experimental conditions, when the laser shock times or laser energy increases, the peak impact force and impact return velocity also increase, whereas the absorbed energy and wear volume decrease. The analysis of variance (ANOVA) results shows that the impact abrasive wear resistance of LSP-treated TC4 alloy is significantly improved when the laser energy reaches 7 J and the laser shock times reach three times. The relationship between the absorbed energy and wear volume of the specimens was also qualitatively analyzed. A high energy absorption indicates great loss of material. The wear mechanism under the no-sand environment mainly comprises cracking, spalling, delamination, and scratching. Meanwhile, the wear mechanism under the sand environment is mainly characterized by ploughing, micro-cutting, and sand embedding on the surface of the specimens.