Effect of elastic strain energy on the core-shell structures of the precipitates in Al-Sc-Er alloys  

作　　者：陈思成 李长荣 连广丽 郭翠萍 杜振民 

机构地区：[1]School of Materials Science and Engineering,University of Science and Technology Beijing

出　　处：《Journal of Rare Earths》2012年第12期1276-1280,共5页稀土学报（英文版）

基　　金：Project supported by National Natural Science Foundation of China (50731002, 51271027)

摘　　要：The effect of the elastic strain energy on the core-shell structures was studied in an Al-0.06Sc-0.02Er （at.%） alloy. A theoretical model for the calculation of the elastic strain energy caused by core-shell precipitates, which is applicable to materials with weak elastic anisotropy, was adopted. It was demonstrated that the partitioning of Er to the precipitate core did not reduce the elastic strain energy as expected in the previous study. The resistance due to the elastic strain energy to form an Al3（Sc0.36Ero.64）-Al3（Sc0.8Er0.2） core-shell precipitate was quite small, and could be easily overcome by the decrease of the total interracial energy, which was consistent with the previous experimental results. On the other hand, the resistance due to the elastic strain energy to form an Al3Er-Al3Sc core-shell precipitate was much larger than that to form an Al3（Sc0.36Er0.64）-Al3（Sc0.8Er0.2） core-shell precipitate, thus the partitioning of all the Er atoms to the core was strongly hindered by the elastic strain energy and was not observed in the experiment of the previous study.The effect of the elastic strain energy on the core-shell structures was studied in an Al-0.06Sc-0.02Er （at.%） alloy. A theoretical model for the calculation of the elastic strain energy caused by core-shell precipitates, which is applicable to materials with weak elastic anisotropy, was adopted. It was demonstrated that the partitioning of Er to the precipitate core did not reduce the elastic strain energy as expected in the previous study. The resistance due to the elastic strain energy to form an Al3（Sc0.36Ero.64）-Al3（Sc0.8Er0.2） core-shell precipitate was quite small, and could be easily overcome by the decrease of the total interracial energy, which was consistent with the previous experimental results. On the other hand, the resistance due to the elastic strain energy to form an Al3Er-Al3Sc core-shell precipitate was much larger than that to form an Al3（Sc0.36Er0.64）-Al3（Sc0.8Er0.2） core-shell precipitate, thus the partitioning of all the Er atoms to the core was strongly hindered by the elastic strain energy and was not observed in the experiment of the previous study.

关 键 词：aluminum alloys PRECIPITATION core-shell structure elastic strain energy rare earths 

分 类 号：TG146.21[一般工业技术—材料科学与工程]