微量稀土对Al-Zn-Mg-Cu-Zr合金力学性能与腐蚀性能的影响（英文）

Effect of Rare Earth Metals on Mechanical and Corrosion Properties of Al-Zn-Mg-Cu-Zr Alloy

采用慢应变速率拉伸试验、显微硬度和电导率测试、晶间腐蚀和剥落腐蚀试验、光学显微镜、扫描电镜、透射电镜等分析方法,研究微量稀土对7085铝合金(Al-7.5Zn-1.5Mg-1.4Cu-0.15Zr)力学性能和腐蚀性能的影响。结果表明,与未添加稀土的合金相比,添加微量稀土使合金组织细化,时效后强度硬度提高。同时,合金的耐腐蚀性明显提高,其中抗晶间腐蚀性能由4级提高为2级、48 h下的剥落腐蚀性能由EB提高为PA、反映应力腐蚀性能的ISSRT值由65%提高到96%。

The effect of rare earth metals on mechanical and corrosion properties of 7085 aluminum alloy（Al-7.5Zn-1.5Mg-1.4Cu-0.15Zr） was investigated by means of optical microscopy（OM）, scanning electron microscopy（SEM） and transmission electron microscopy（TEM）. Intergranular, exfoliation corrosion, hardness, tensile test and electrical conductivity test were performed Al alloys on both with and without rare earth additives. Results show the Al alloys with rare earth metals present better mechanical properties such as higher strength and hardness as a result of finer microstructure in comparison with those without the additives. The corrosion resistance is greatly improved by adding rare earth metals. Intergranular corrosion resistance is enhanced from Level IV to Level II, the denudation level for 48 h is improved from EB to PA and ISSRT reflecting stress corrosion resistance was enhanced from 65% to 96%.