激光冲击强化改善2A12高强铝合金疲劳寿命的试验研究  

Experimental study on fatigue life enhancement of high-strength Al alloy by laser shock process

作　　者：张乐[1] 袁海洋[1] 游张平[2] 

机构地区：[1]湖南信息职业技术学院机电工程系,湖南长沙410200 [2]丽水学院工程与设计学院,浙江丽水323000

出　　处：《轻金属》2017年第3期39-41,共3页Light Metals

基　　金：湖南省教育厅科学研究项目(13C653);丽水高层次人才培养资助项目(2015RC28);省公益性技术应用研究计划项目(2016C31053)

摘　　要：采用激光冲击强化工艺对2A12铝合金试件进行表面处理,借助先进的测试方法分析试件表层显微硬度、残余应力与表面变形量的分布特点,并研究低应力下的高周疲劳寿命改善效果。结果表明,激光冲击强化可在试件表层引入较浅的显微硬度与残余应力影响层及较为显著的表面变形量,随激光能量增大则其影响程度增加且呈现出中心均匀边缘非均匀的特点。表层残余应力场是改善试件疲劳寿命的最主要因素。The surface of 2A12 high - strength AI alloy specimens were treated by laser shock process. The micro - hardness, residual stress and deforma- tion distribution were measured by advanced measurement methods, and high - cycle fatigue life enhancement under low stress were also studied. The re- suits show that the influence micro - hardness and residual stress is moderate but the deformation is obvious, More powerful laser energy leads to larger mi- cro - hardness, residual stress and deformation, and the characteristics of stresses and deformations are homogeneous in central region and heterogeneous in marginal regions. Moreover, the residual stress filed on the surface is the main reason in enhancing fatigue life.

关 键 词：铝合金 激光冲击强化 显微硬度 残余应力 变形 疲劳寿命 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG665[金属学及工艺—金属材料]