微量Sc和Zr对7A55合金铸锭组织的细化机理

来源期刊：中南大学学报(自然科学版)2005年第6期

论文作者：贺永东 张新明 陈健美 唐建国

文章页码：919 - 923

关键词：Sc; Zr; 7A55合金;非均质晶核;细化作用

Key words：Sc; Zr; 7A55 alloy; heterogeneous nucleation; grain refinement

摘    要：采用光学显微镜和扫描电镜研究了微量Sc和Zr元素对7A55合金铸锭组织的细化作用及其细化机理。研究结果表明:单独添加微量的Sc或Zr对7A55合金铸锭组织均有一定的细化作用,而复合添加0. 10% Sc+0. 20% Zr则对7A55合金铸锭组织产生强烈的晶粒细化作用。当Sc和Zr添加量分别达到0. 30%和0. 18%时,铸锭平均晶粒尺寸仅为10~15μm, Al3Sc/Al3Zr质点对7A55合金起了非均质晶核细化晶粒的作用。

Abstract: The effectof trace Sc and Zron grain refinementof7A55 as-cast ingotwas studied byusing optical microscopy and scanning electron microscopywith EDS. The results show that addition of only 0.18% Zr or 0. 18% Sc to 7A55 alloy can refine grains to a certain degree, and the addition of0. 10% Sc+0. 20%Zr leads to stronger grain refinemen.t When 0. 30% Sc and 0. 18% Zr are added to 7A55 alloy,the average grain size is only10 15μm. Al3Sc/Al3Zr composite particles in themeltwork as the nucleus ofheterogeneous nucleation during solidification.

基金信息：国家重点基础研究发展规划项目