摘要
本文以钛合金材料为研究对象,对温度辅助激光冲击材料的残余应力分布规律进行了研究,在试样表面温度为20℃、105℃、305℃、405℃下,使用Nd:YAG纳秒激光器分别对TC4钛合金试样进行激光喷丸表面强化,在高周疲劳条件下使用疲劳试验机对试样进行疲劳寿命测试和残余应力释放测试。实验表明,经过10050次循环载荷后,在试样表面温度为20℃、105℃、305℃、405℃时,激光喷丸TC4钛合金残余压应力幅值分别为-100 MPa、-70 MPa、-190 MPa、-152 MPa。在305℃时,激光温喷丸试样发生断裂时,轴向位移比未喷丸试样要明显高;与未喷丸试样相比,发生断裂时轴向位移比提高36.98%,且激光温喷丸试样屈服强度要比其它试样显著高,增加了其断裂韧性;在305℃时,激光温喷丸试样疲劳寿命最大值为147975次,是20℃激光喷丸的1.68倍。
In this paper,the distribution of residual stress in temperature-assisted laser shock material was studied.The surface of TC4 titanium alloy was strengthened by laser peening with Nd:YAG nanosecond laser at surface temperatures of 20℃,105℃,305℃and 405℃,respectively,under high cycle fatigue conditions.The fatigue life test and residual stress release test of the specimens were carried out by using a fatigue testing machine.The experimental results show that the residual compressive stress amplitudes of laser shot peening TC4 titanium alloy are-100 MPa,-70 MPa,-190 MPa,-152 MPa,respectively,at surface temperatures of 20℃,105℃,305℃and 405℃after 10050 cycles of loading.The axial displacement of laser warm shot peening specimens is higher than that of non-shot peening specimens at 305℃.Compared with non-shot peening specimens,the axial displacement ratio increases by 36.98%,and the yield strength of laser warm shot peening specimens is significantly higher than that of other specimens,which increases the fracture toughness.The maximum fatigue life of the sample is 147975 times,which is 1.68 times of that of laser shot peening at 20℃.
作者
张慧
Zhang Hui(Jiangsu Vocational College of Medicine,YunCheng,Jiangsu 224005,China)
出处
《应用激光》
CSCD
北大核心
2020年第3期430-434,共5页
Applied Laser
基金
江苏省高层次人才"六个一工程"项目(项目编号:LGY2018088)。
关键词
激光冲击
分布规律
温度
残余应力
钛合金
laser shock
distribution law
temperature
residual stress
titanium alloy
