7050铝合金在EXCO溶液中的腐蚀与氢脆对拉伸性能的影响

Effect of Corrosion and Hydrogen Embrittlement on Tensile Properties of 7050 Aluminum Alloy in EXCO Solution

采用金相显微镜、慢应变速率拉伸试验(SSRT)、定氢仪、透射电镜等研究了7050铝合金在EXCO溶液中的腐蚀与氢脆行为及其对合金拉伸性能的影响。结果表明:随着合金在溶液中浸泡时间的延长,腐蚀特征由点蚀向剥蚀发展,并且有氢脆效应产生。腐蚀和氢脆共同作用大大降低了合金的拉伸性能。通过去除腐蚀层后继续拉伸定量分析了氢脆影响下合金的剩余强度和延伸率,当浸泡时间达64 h时,氢脆使合金的剩余强度和延伸率分别降至68.2%和60.2%。

The corrosion and hydrogen embrittlement behavior as well as their influence on the tensile properties of 7050 aluminum in EXCO solution have been investigated by means of metallographic microscope,slow strain rate testing（SSRT）,hydrogen determinator and transmission electron microscope.The results show that the corrosion characteristic develops from pitting to exfoliation with immersion time increasing,and the hydrogen embrittlement effect occurs,too.The combined action of corrosion and hydrogen embrittlement reduces the tensile properties of the alloy to a large degree.The alloy’s residual strength and elongation affected by hydrogen embrittlement have been quantitatively analyzed by tensile tests after removing the corrosion layer.When the immersion time reaches 64 h,the residual strength and elongation influenced only by hydrogen embrittlement decrease to 68.2%and 60.2%,respectively.