铝青铜在3.5%NaCl溶液中的脱成份腐蚀行为

CORROSION BEHAVIOR OF Al-BRONZE IN 3.5% NaCl SOLUTION

用电化学方法和表面分析技术对铝青铜的脱成份腐蚀行为进行研究 .结果表明 ,铝青铜系合金中亚稳态的 β相与α相基体相比 ,具有明显的优先腐蚀倾向 ,这主要是亚稳的 β相组织的含Al量高于α相造成的 .在阳极活性溶解区 ,由于 β相中的Al元素溶解造成合金表面产生了点蚀坑 ,在阳极活化 -钝化转化区 β相中的Al元素大量溶解 ,β相腐蚀严重 .β相溶解电位正移接近α相溶解电位 ,α相开始发生腐蚀 ,在极限电流区 ,材料表面α相成为富铝相 (即阳极区 ) ,也发生严重的脱铝腐蚀 ,α相和 β相中的其它合金元素也发生腐蚀脱落 .

The corrosion behavior of Al-bronze in 3.5% NaCl solution has been investigated by electrochemical methods and surface analysis techniques.The results indicated that the metastable β phase suffers a dealuminization attack superior to the α matrix in the Al-bronze alloy because the β phase own more Al content than that of the α matrix.In the active dissolution section,the impingement appearing owns to the Al element dissolution of the β phase.In the active -passive translation section,most of the Al in the β phase dissolve.The dissolution potential of the phase β moves positively and the α matrix begins to dissolve.In the limiting current section,the α matrix is the rich Al phase,the anodic section, and suffers serious dealuminization corrosion.