新型超高强Cu−Ni−Al−Si合金在r3.5NaCl溶液中的腐蚀行为

摘要

设计并制备了一种新型超高强Cu?6.5Ni?1Al?1Si?0.15Mg?0.15Ce合金,采用扫描电镜观察、透射电镜观察、光电子能谱分析等手段研究该合金在3.5%NaCl溶液中的腐蚀行为.合金经固溶、冷轧80%并在450℃时效1 h后具有最佳的综合性能,其硬度为HV 314,导电率为19.4%IACS,抗拉强度为1017 MPa,年平均腐蚀速率为0.028 mm/a.腐蚀初期合金表面形成了氧化腐蚀产物和氯化腐蚀产物,随着腐蚀时间延长形成了氢氧化物腐蚀产物.合金具有超高的强度、优良的导电率和耐腐蚀性能是由于Ni2Si能够抑制晶界处粗大NiAl相的析出,并能抑制合金的脱Ni腐蚀.%A novel Cu?6.5Ni?1Al?1Si?0.15Mg?0.15Ce alloy with super-high strength was designed and its corrosion behavior in 3.5% NaCl solution at 25 ℃ was investigated by the means of SEM observation, TEM observation and XPS analysis. The alloy after solution treatment, 80% cold rolling and aging at 450 °C for 1 h had the best comprehensive properties with hardness of HV 314, electrical conductivity of 19.4% IACS, tensile strength of 1017 MPa, and average annual corrosion rate of 0.028 mm/a. The oxides and chloride products formed at first, followed by the formation of dyroxides products. The alloy showed super-high strength, good electrical conductivity and corrosion resistant because Ni2Si hindered the precipitation of large NiAl at the grain boundary and the denickelefication of the alloy.