陶瓷喷丸强化对TC4-DT钛合金疲劳性能的影响

Effect of Ceramic Shot Peening on Fatigue Properties of TC4-DT Titanium Alloy

为了探讨陶瓷丸喷丸强化对TC4-DT钛合金疲劳行为的影响,对TC4-DT钛合金进行了铸钢喷丸强化和陶瓷喷丸强化,采用表面轮廓仪、扫描电子显微镜、旋转弯曲疲劳、轴向疲劳等研究了2种喷丸介质对TC4-DT钛合金表面粗糙度、表面形貌、表面残余压应力、疲劳寿命、疲劳强度的影响。结果表明:陶瓷丸喷丸对TC4-DT钛合金疲劳极限影响不大,陶瓷丸喷丸后表面形貌和粗糙度明显优于铸钢丸喷丸表面,陶瓷丸喷丸强化效果优于铸钢丸喷丸,可提高疲劳寿命达20倍以上。对于薄壁零件喷丸强化,陶瓷喷丸强度不宜超过0.15 A,喷丸强度过高,强化效果不佳。

In order to investigate the effect of ceramic shot peening on the fatigue behavior of TC4-DT titanium alloy,cast steel shot peening and ceramic shot peening were carried out on TC4-DT titanium alloy.The surface roughness,surface morphology,surface residual compressive stress,fatigue life and fatigue strength of TC4-DT titanium alloy by two kinds of shot peening materials were studied by surface profiler,scanning electron microscope,rotary bending fatigue and axial fatigue.Results showed that ceramic shot peening had little effect on the fatigue limit of TC4-DT titanium alloy.The surface morphology and roughness after ceramic shot peening were obviously better than those after cast steel shot peening.Moreover,the strengthening effect of ceramic shot peening was better than that of cast steel shot peening,and the fatigue life was increased by more than 20 times.As for thin-walled parts,the shot peening strength of ceramics should not exceed 0.15 A.If the shot peening strength was too high,the strengthening effect was not good.