QAl9-2合金脱铝腐蚀的TEM研究

TEM observation on dealuminification corrosion of QAl9-2 alloy in marine environment

针对QAl9 2合金在海洋环境中亚稳 β1相优先脱铝腐蚀的问题 ,利用TEM ,EDX以及XRD分析 ,对其发生脱铝和未发生脱铝的区域进行了细致的研究。结果表明 ,QAl9 2合金的脱铝腐蚀与亚稳 β1相的马氏体相变有关 ,腐蚀优先发生在相变产物片状 β′1相区 ,β′1马氏体相的优先腐蚀是由有序的DO3 结构及其内部存在的大量层错造成的。

In view of preferential dealuminification corrosion of metastable β 1 phase, QAl9 2 alloy before and after dealuminification in marine environment was studied by TEM, EDX and XRD analysis. It was indicated that the dealuminification corrosion of QAl9 2 alloy is associated with martensite transformation of metastable β 1 phase, and occurs within the transformation products, β ′ 1 martensite plates. The reason is that there are DO 3 structure and a large amount of stacking faults in the β ′ 1 martensite plates. Micro pits and aluminum rich fine corrosion products were also observed by TEM. [