硝酸含量对测量5xxx铝合金板材晶间腐蚀性能的影响

使用不同含量硝酸溶液对5052-H112、5454-H111和5083-H116铝合金板材进行晶间腐蚀敏感性测试。结果表明,使用质量损失法对5xxx铝合金晶间腐蚀敏感性进行测量时,硝酸含量对试验结果影响很大,对比硝酸含量分别为44%、65%和71%(质量分数)时的质量损失,44%最大、65%次之、71%最小,表明使用71%的硝酸对三种铝合金测量的晶间腐蚀敏感性弱于使用44%和65%的硝酸;因此可以使用我国的分析纯硝酸代替ASTM G67-2013标准中要求的硝酸含量对5xxx铝合金板材晶间腐蚀敏感性的测定,以及GB/T 26491-2011标准比ASTM G67-2013标准更加苛刻。

Effect of Nitric Acid Content on Intercrystalline Corrosion of 5xxx Aluminum Alloy Plates

In this paper,the intercrystalline corrosion susceptibility of 5052-H112,5454-H111 and 5083-H116 aluminum alloy plates is tested with nitric acid solutions of different contents.The results show that the nitric acid content has a great influence on the test results when the mass loss method is used to measure the intercrystalline corrosion susceptibility of 5xxx aluminium alloy.Compared with the mass loss of 44%,65% and 71%(wt.%)nitric acid content,44% is the largest,65%is the second and 71%is the smallest.The results show that 71%nitric acid is less sensitive to intercrystalline corrosion than 44% and 65% nitric acid.Therefore,the analysis of pure nitric acid in China can be used to instead of ASTM G67-2013 standard,which requires the determination of nitric acid content to the intercrystalline corrosion sensitivity of 5xxx aluminum alloy plates,and GB/T 26491-2011 standard is more stringent than ASTM G67-2013 standard.