喷丸状态对受损铝合金抗应力腐蚀的影响  

Effects of shot peening on anti-stress corrosion of aluminum alloy

作　　者：邓红华[1] 程秀全[1] 夏琴香[2] 

机构地区：[1]广州民航职业技术学院飞机维修工程学院,广东广州510470 [2]华南理工大学机械与汽车工程学院,广东广州510640

出　　处：《轻合金加工技术》2016年第8期53-58,共6页Light Alloy Fabrication Technology

基　　金：国家自然科学基金资助项目(51575117);国家自然科学基金(民航联合基金)资助项目(61179051)

摘　　要：为分析喷丸状态对铝合金腐蚀损伤构件表面的应力腐蚀性能影响,采用四面、双面、不喷丸的7075铝合金试样,通过改变腐蚀溶液NaCl浓度、腐蚀溶液pH值、腐蚀温度、腐蚀时间以获得不同程度的腐蚀损伤,再将五类不同喷丸表面状态的铝合金试样进行慢拉伸速率试验对比。结果表明,预腐蚀前若进行四面喷丸,则铝合金的屈服强度、屈服应变、抗拉强度、断裂载荷分别提高了3.92%、0.60%、4.72%、9.52%。而抗拉强度对应的应变值、伸长率则分别降低了10.92%、15.26%。预腐蚀后若再次进行四面喷丸,则这些性能还会进一步提升或下降;相对于四面喷丸,双面喷丸试样应力腐蚀性能的变化小;腐蚀溶液NaCl浓度、腐蚀溶液pH值、腐蚀温度、腐蚀时间对应力腐蚀性能的影响程度为:pH值对屈服强度、抗拉强度、伸长率影响最小,温度对屈服强度影响最大,时间对抗拉强度、伸长率影响最大。In order to investigate the influence of shot peening on stress corrosion performance of aluminum alloy corrosion-damage components, 7075 aluminum alloy samples are taken to be shot peened on four sides, two sides and none side ; different degrees of corrosion is obtained with various corrosive NaC1 concentrations, pH values, temperatures and time; then slow strain-rate tests are carried out on aluminum alloy samples with five different shotpeened surface states. The results show that if the sample is shot peened on four sides before pre-corrosion, yield strength, yield strain, tensile strength and breaking load of aluminum al- loy increase by 3.92% ,0.60% ,4.72% and 9.52% respectively,while the strain value cor- responding to tensile strength,and elongation decrease by 10.92% and 15.26% accordingly. If the sample is shot peened on four sides after pre-corrosion, these properties would be further improved or declined. For the sample with two-side shot peening, the stress corrosion performance changes more slightly than that of the sample with four-side shot peening. Yield strength,tensile strength and elongation are least influenced bv DH value, vield strength is most influenced by temperature, and tensile strength and elongation are most influenced by time.

关 键 词：喷丸 表面状态 铝合金 预腐蚀处理 应力腐蚀 

分 类 号：TG668[金属学及工艺—金属切削加工及机床] TG146.21[一般工业技术—材料科学与工程]