摘要
通过显微硬度测试及三维原子探针(3DAP)分析对Al-0.03Er、Al-7.7Li、Al-0.03Er-7.7Li (at%)合金的时效强化与显微组织进行了研究。结果表明,Al-0.03Er合金在350℃等温时效10 min达到峰时效硬度38HV,相比固溶态硬度提升了12 HV。Al-7.7Li合金在190℃等温时效24 h达到峰时效硬度98 HV,相比固溶态提升了56 HV。Al-0.03Er-7.7Li合金经350℃/1 h+190℃/8h双级时效后,硬度达108 HV,相比固溶态提升了66 HV,其强化效果为Al-0.03Er、Al-7.7Li合金强化效果的叠加。对此状态的Al-Er-Li合金显微组织进行分析,结果表明,合金中有3种析出相:Al3Er、Al3Li及以Al3Er为核、Al3Li为壳的Al3(Er,Li)相,说明先析出的Al3Er能作为Al3Li异质形核的核心,从而促进了Al3Li的析出,使Al-Er-Li合金强度高于Al-Li合金的强度。
The aging strengthening and microstructure of the Al-0.03Er, Al-7.7Li, Al-0.03Er-7.7Li alloys were studied by microhardness test and 3 DAP analysis. The results show that, the peak-aging hardness of Al-0.03Er alloy is 38 HV when it is aged at 350 ℃ for 10 min, and compared with that of the solid solution alloy, the hardness of Al-0.03Er is increased by 12 HV. Al-7.7Li alloy reaches peak aging hardness of 98 HV after isothermal aging at 190 ℃ for 24 h, which increases 56 HV compared that of the alloy in with solid solution state. The hardness of Al-0.03Er-7.7Li alloy aged at 350 ℃/1 h, 190 ℃/8 h reaches 108 HV, which is 66 HV higher than that of the solid solution alloy. The strengthening effect is the superposition of Al-0.03Er and Al-7.7Li alloy. The microstructure of the Al-Er-Li alloy in the state was analyzed. The results show that, there are three kinds of precipitated phases: Al3Er, Al3Li and Al3(Er,Li) with Al3Er as core and Al3Li as shell. It shows that the Al3Er can be the core of the Al3Li heterostructure nucleus. Thus, the precipitation of Al3Li is promoted, and the strength of Al-Er-Li alloy is higher than that of Al-Li alloy.
作者
刘琦兵
高坤元
聂祚仁
丁宇升
LIU Qibing;GAO Kunyuan;NIE Zuoren;DING Yusheng(School of Materials Science and Engineering,Beijing University o f Technology,Beijing 100124,China)
出处
《热加工工艺》
北大核心
2020年第14期111-113,118,共4页
Hot Working Technology
基金
国家科技部重点研发项目(2016YFB030081)
北京市自然科学基金项目(2162006)。
