摘要
目前,鲜见有关对AZ31镁合金采用搅拌摩擦加工改善其微观形貌进而提高其耐蚀性能的报道。采用电化学测试仪、光学显微镜、扫描电镜及分析天平研究了AZ31镁合金搅拌摩擦加工前后在3.5%NaCl溶液中的腐蚀行为。结果表明:在含Cl-溶液中,与原材AZ31相比,加工后的AZ31自腐蚀电位较高,自腐蚀电流密度较小,阻抗较大,且腐蚀失重速率较小,两者的腐蚀机制均为点蚀,加工后的AZ31点蚀程度较轻,形成了细小的等轴晶及第二相的固溶,提高了其耐蚀性能。
The corrosion behavior of AZ31 Mg alloy betore and after friction-stir processing in 3.5%NaCl solution was evaluated with an electrochemical tester,an optical microscope,a scanning electron microscope and an analytical balance.It was found that,in Cl^-containing solution,Mg alloy after friction-stir processing exhibited higher corrosion potential,smaller corrosion current density,and higher impedance than untreated Mg alloy,and the former exhibited smaller corrosion- induced weight loss rate as well.Moreover,both untreated Mg alloy and treated Mg alloy were dominated by pitting,and the treated one underwent slighter pitting and exhibited better corrosion resistance,due to the formation of fine equiaxed grains and second phase solid solution.
出处
《材料保护》
CAS
CSCD
北大核心
2014年第2期27-29,47,共4页
Materials Protection
基金
广东省重大科技专项(2008A090300004)
广东省教育厅211工程学科建设项目
关键词
搅拌摩擦
AZ31镁合金
耐腐蚀性
点蚀
friction-stir processing
AZ31 magnesium alloy
corrosion resistance
pitting
