7075型铝合金在含NaOH碱性NaCl溶液中的腐蚀行为  

Corrosion Behavior of Aluminum Alloy in Alkaline Sodium Chloride Solution Containing Sodium Hydroxide

作　　者：胡博[1] 王建朝[1] 刘影[1] 赵美峰[1] 陆军[1] 黄岩[1] 

机构地区：[1]青海师范大学化学系,青海西宁810008

出　　处：《材料保护》2014年第3期23-27,36,共6页Materials Protection

基　　金：国家自然科学基金资助项目(51061016)

摘　　要：为进一步了解7075型铝合金在碱性工作环境中的腐蚀行为，采用电化学方法研究了NaOH浓度、Cl-含量和温度对7075型铝合金在高低NaOH浓度的碱性NaCl溶液中的腐蚀行为。结果表明：低NaOH浓度（0．1-0．5mol/L）时．铝合金表面以阻挡层（腐蚀产物附着层）的生长为主，NaOH浓度越高，阻挡层生成速率越大；高NaOH浓度（1．0～5．0mol／L）时。铝合层表面以阻挡层的溶解为主，NaOH浓度越高，阻挡层受析氢破坏的程度越大；析氢对阻挡层的破坏作用在Cl-作用下有所加强，溶液中NaOH浓度越高，增强效果越明显；在0．04mol／，LNaOH＋0．01mol／LNaCl溶液中，温度主要影响阻挡层的生长，其生长速率随温度的升高而增加，在0．40mol／，LNaOH＋0．01NaCl溶液中，温度主要影响阻挡层的溶解，阻挡层受析氢破坏程度随温度升高而加大。The corrosion behavior of 7075 Al alloy in alkaline NaCl solution containing different concentration of NaOH was investigated by electrochemical method,and the effects of NaOH concentration and Cl-content as well as temperature on the corrosion behavior were explored. Results indicated that,at lower NaOH concentration( 0. 1 ~ 0. 5 mol /L),the growth of barrier layer( the adhered layer of corroded products) was dominant on Al alloy surface,and the growth rate of the barrier layer rose with increasing NaOH concentration. Besides,at higher NaOH concentration( 1. 0 ~ 5. 0 mol /L),the dissolution of the barrier layer was dominant on Al alloy surface,and the degree of destruction of the barrier layer caused by hydrogen evolution rose with NaOH concentration. In the meantime,the presence of Cl-accelerated the hydrogen-evolution-induced damage of the barrier coating to some extent,and such an accelerating function augmented with elevating NaOH concentration. Moreover,in the solution consisting of 0. 04 mol /L NaOH and 0. 01 mol /L NaCl,temperature mainly influenced the growth of the barrier coating,and the growth rate of the barrier coating rose with elevating temperature.In the solution consisting of 0. 40 mol /L NaOH and 0. 01 NaCl,however,temperature mainly influenced the dissolution of the barrier layer,and the degree of hydrogen-evolution-induced damage of the barrier layer augmented with elevating temperature.

关 键 词：7075铝合金 碱性NaCl溶液 腐蚀行为 NaOH浓度 

分 类 号：TG172[金属学及工艺—金属表面处理]