喷砂处理对A7N01铝合金应力腐蚀开裂和点蚀性能的影响  

Influence of Sand Blasting Treatment on Stress Corrosion Cracking and Pitting Corrosion Properties of A7N01 Aluminum Alloy

作　　者：李明星[1] 廖潇垚 王晓敏[1] 郭强军[2] 陈辉[3] 

机构地区：[1]西南交通大学生命科学与工程学院,成都610031 [2]南车青岛四方机车车辆股份有限公司,青岛266111 [3]西南交通大学材料科学与工程学院,成都610031

出　　处：《腐蚀与防护》2017年第9期683-688,共6页Corrosion & Protection

基　　金：四川省科技支撑计划资助项目(2016GZ0239)

摘　　要：采用慢应变速率试验和循环极化试验,研究了喷砂对A7N01铝合金耐应力腐蚀开裂和点蚀性能的影响。结果表明:在3.5%NaCl(质量分数)溶液中,与未喷砂合金相比,喷砂处理后A7N01铝合金的应力腐蚀敏感指数增大,抗应力腐蚀性能下降。喷砂后合金的点蚀电位、保护电位均降低,滞后环增大,且随浸泡时间增长,点蚀电位和保护电位负移,滞后环增大,喷砂处理使合金的抗点蚀能力和钝化膜修复能力降低。喷砂处理会造成A7N01铝合金表层晶粒细化、硬度增加,但同时喷砂也会造成表面粗糙度增加,并有微裂纹等表面损伤发生,从而降低合金的耐蚀性。The influence of sand blasting treatment on the stress corrosion cracking （SCC） property and pitting property of A7N01 aluminum alloy was investigated by slow stain rate test （SSRT） and circular polarization test. The results showed that the SCC sensitive indexes （IssRT） and SCC sensitivity of treated alloy in 3. 5 % NaC1 was higher than those of untreated alloy. The pitting potential （Eb） and protective potential （Ep） of treated alloy were lower than those of untreated alloy and the area of hysteresis loop was larger. With increasing the soaking time, Eb and Ep shifted negatively and the area of hysteresis loop increased. This implied that the anti-pitting property and selfrep.airing property of A7N01 alloy decreased after sand blasting treatment. The treatment made the surface layer microhardness increase and the surface grains refine. However, the treatment led to the increase of surface roughness and the formation of micro-cracks on surface, which was harm to the anti-corrosive property of A7N01 A1 alloy.

关 键 词：高速列车 A7N01铝合金 喷砂处理 应力腐蚀开裂 点蚀 

分 类 号：TG174.2[金属学及工艺—金属表面处理]