7075铝合金瞬时腐蚀速率的计算和试验验证  

Experimental Evaluation of Computing Method of Instantaneous Corrosion Rate for 7075 Aluminum Alloy

作　　者：陈素晶[1] 袁庆铭[2] 何建平[1] 周建华[1] 

机构地区：[1]南京航空航天大学材料科学与技术学院,南京210016 [2]厦门航空有限公司,厦门361009

出　　处：《材料工程》2004年第12期43-46,共4页Journal of Materials Engineering

摘　　要：针对铝合金腐蚀平均速率与瞬时速率的差异,根据腐蚀过程中试样横截面的变化与欧姆电阻的对应关系,建立了新的腐蚀速率计算方法。将试样全浸和半浸在腐蚀溶液中,分别测定了7075铝合金电阻随时间的变化,并由腐蚀速率计算公式获得了对应的腐蚀速率与时间的关系。结果表明,全浸6h前铝合金腐蚀速率随时间线性减小,接下来经历一个平坦区,25h后腐蚀速率又稍微增加。推断全浸6h之前铝合金表面主要发生点蚀,接下来是晶间腐蚀,25h之后进入剥蚀的发展期。铝合金半浸于电解液中的腐蚀速率随时间的变化趋势与全浸于溶液中相似。WT5BZ]Based on the relationship between cross section variety and resistance of sample, a new formula was put forward to calculate the instantaneous corrosion rate of aluminum alloy.Ohm resistance of 7075 aluminum alloy was measured while alloy was immersed entirely or half in corrosion electrolyte, then corrosion rate of the alloy was calculated with the new formula. The results showed that corrosion rate of 7075 aluminum alloy in electrolyte linearly decreased before 6h,got to a flat region,and little increased after 25h. These three periods corresponded to pitting, intergranular corrosion and exfoliation of sample. Corrosion rate of aluminum alloy half-immersed in electrolyte with time was similar with that of sample immersed entirely in electrolyte.

关 键 词：电阻法 铝合金 腐蚀速率 瞬时 

分 类 号：TG174.3[金属学及工艺—金属表面处理]