Effects of lanthanum addition on microstructure and mechanical properties of as-cast pure copper  

作　　者：陈岩 程明 宋鸿武 张士宏 刘劲松 祝焱 

机构地区：[1]Institute of Metal Research, Chinese Academy of Sciences [2]School of Materials Science and Engineering, Shenyang Ligong University [3]Guangdong Longfeng Precise Tube Co., Ltd.

出　　处：《Journal of Rare Earths》2014年第11期1056-1063,共8页稀土学报（英文版）

基　　金：Project supported by Science Foundation of The Chinese Academy of Sciences

摘　　要：As-cast Cu-La alloys with La contents in the range of 0–0.32 wt.% were fabricated by vacuum melting method. The effects of La on microstructure and mechanical properties of as-cast pure copper were investigated using optical microscopy（OM）, scanning electronic microscopy（SEM）, transmission electron microscopy（TEM）, X-ray diffraction（XRD） and tensile test. The results showed that La had obvious effects on the solidification microstructure and the grain refinement of as-cast pure copper. With the increase of La content, the ultimate tensile strength, the yield strength and the microhardness increased gradually, but the elongation increased first and then decreased while La content exceeded 0.089 wt.%. The improvement of mechanical properties was attributed to the effect of grain refinement strengthening, solid solution strengthening, second phase strengthening and purifying. However, excessive adding La would deteriorate the elongation owing to the excessive Cu6 La phases.As-cast Cu-La alloys with La contents in the range of 0–0.32 wt.% were fabricated by vacuum melting method. The effects of La on microstructure and mechanical properties of as-cast pure copper were investigated using optical microscopy（OM）, scanning electronic microscopy（SEM）, transmission electron microscopy（TEM）, X-ray diffraction（XRD） and tensile test. The results showed that La had obvious effects on the solidification microstructure and the grain refinement of as-cast pure copper. With the increase of La content, the ultimate tensile strength, the yield strength and the microhardness increased gradually, but the elongation increased first and then decreased while La content exceeded 0.089 wt.%. The improvement of mechanical properties was attributed to the effect of grain refinement strengthening, solid solution strengthening, second phase strengthening and purifying. However, excessive adding La would deteriorate the elongation owing to the excessive Cu6 La phases.

关 键 词：as-cast pure copper La MICROSTRUCTURE mechanical property rare earths 

分 类 号：TG146.11[一般工业技术—材料科学与工程] TG255[金属学及工艺—金属材料]