HAl77-2铝黄铜添加微量Cr后的耐腐蚀性能  

Effect of Chromium on Corrosion Resistance of Aluminum Brass

作　　者：曾德露[1] 肖来荣[1,2] 赵小军[1] 王彦红[1] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]有色金属材料科学与工程教育部重点实验室(中南大学),湖南长沙410083

出　　处：《材料保护》2014年第12期47-49,51,共4页Materials Protection

基　　金：广东省教育部产学研结合项目(2012A090300008)资助

摘　　要：为了提高HAl77-2铝黄铜在海水和工业冷却水中的耐蚀性,添加微量Cr制成合金。通过测定6种不同Cr含量的铝黄铜在3.5%Na Cl溶液和3.5%Na Cl+0.5 mol/L NH4Cl溶液中的腐蚀速率、电化学行为,以及对腐蚀后样品进行扫描电镜(SEM)观察和能谱分析,研究了Cr元素的添加对铝黄铜合金腐蚀行为的影响。结果表明:Cr一方面在合金表面形成钝化膜,提高合金耐蚀性能,另一方面发生团聚,降低合金耐蚀性能;含0.65%Cr的HAl77-2铝黄铜在3.5%Na Cl溶液中有较佳的耐蚀性能,Cr不能改善铝黄铜在3.5%Na Cl+0.5 mol/L NH4Cl溶液中的耐蚀性能。Atrace amount Cr was introduced into HAI77-2 aluminum- brass(denoted as Al-Cu) so as to improve its corrosion resistance in seawater and industrial cooling water.The corrosion rate and electrochemical behavior of six kinds of Al- Cu samples with different Cr dosage in 3.5%NaCl solution and 3.5%NaCl +0.5mol/L NH_4Cl solution were determined.The morphology and elemental composition of the corroded surfaces of the Al-Cu samples were analyzed by scanning electron microscopy and energy dispersive spectrometry,and the effect of Cr on their corrosion behavior was investigated.It was found that,on the one hand,Cr tended to agglomerate on Al-Cu alloy surface thereby reducing the corrosion resistance;on the other hand,Cr was able to form a passivation film on the alloy surface thereby improving the corrosion resistance.Moreover,the Al-Cu alloy containing 0.65%Cr exhibited good corrosion resistance in 3.5%NaCl,but Cr was unable to improve the corrosion resistance of the Al-Cu alloy in 3.5%NaCl +0.5 mol/L NH_4Cl solution.

关 键 词：腐蚀行为 腐蚀介质 CR 铝黄铜 耐蚀性能 

分 类 号：TG172.5[金属学及工艺—金属表面处理]