喷丸强化与应力因素对2E12-T3铝合金剥蚀行为的影响  

Effect of Shot Peening and Stress on Exfoliation Corrosion of 2E12-T3 Al Alloy

作　　者：叶作彦[1] 刘道新[1] 吴剑[1] 张小明[2] 杨智[2] 雷明霞[2] 

机构地区：[1]西北工业大学腐蚀与防护研究所,西安710072 [2]中航工业第一飞机设计研究院,西安710089

出　　处：《腐蚀科学与防护技术》2013年第6期445-450,共6页Corrosion Science and Protection Technology

基　　金：国家自然科学基金项目(51171154)资助

摘　　要：采用浸泡腐蚀实验、金相分析、扫描电镜和X射线衍射分析等技术研究了喷丸强化和应力因素对2E12-T3铝合金剥蚀行为的影响规律,探讨了作用机理。结果表明,2E12-T3铝合金具有很高的剥蚀敏感性,拉应力会明显增强其剥蚀敏感程度,而压应力则会降低其剥蚀敏感性。采用合理的喷丸强化工艺(喷丸强度取0.15 mmN,覆盖率取100%)能够明显降低2E12-T3铝合金的剥蚀敏感性,有效抑制表面鼓泡和分层现象,归因于喷丸引入了表面残余压应力,同时使表层晶粒细化,晶粒的长宽比降低。过高强度或过大覆盖率的喷丸处理,会使铝合金表面产生较严重的损伤性,降低对2E12-T3铝合金的抗剥蚀性能的改善效果。The effect of shot peening （SP） and stress on the exfoliation corrosion behavlour ot 2E12 A1 alloy was studied by means of exfoliation corrosion test, metallographic analysis, scanning electron microscopy （SEM） and XRD analysis. The results show that 2E12-T3 A1 alloy has a high susceptibility to exfoliation corrosion （EXCO）. Tensile stress reduces the resistance to EXCO while compressive stress improves it. Appropriate SP （intensity 0.15 mmN, coverage 100%） can signifi- cantly reduces the susceptibility of 2El 2-T3 A1 alloy to EXCO and suppresses the formation of blis- ters, which may be due to the refined grain size and residual compressive stress produced by SP treatment on the surface layer. However, SP with extra intensity or coverage can not improve the re- sistance to EXCO due to the seriously damaged alloy surface.

关 键 词：2E12-T3铝合金 喷丸强化 剥落腐蚀 残余应力 应力因素 

分 类 号：TG174[金属学及工艺—金属表面处理]