纳米晶 Al 的快中子辐照效应研究

摘要

Nanocrystalline Al bulks with an average grain size of about 120 nm prepared by pressing Al nanopowders in vacuum were irradiated by fast neutron (E> 1 MeV) with the fluence of 1.9 × 1012‐7.2 × 1014 cm -2 .The effect of fast neutron irradiation on microstructure and microhardness of nanocrystalline Al was analyzed through XRD , SEM‐EDS and microhardness test .The experiment results show that the average grain size increases and the microhardness becomes larger after fast neutron irradiation for nanocrystalline Al .The average grain size and microhardness of nanocrystalline Al after fast neutron irradiation increase 2.09%‐9.09% and 3.54%‐4.37% ,respectively .The increasing rate of the average grain size increases with the fast neutron fluence .%采用真空热压技术将自悬浮定向流法制得的纳米Al粉压制成平均晶粒尺寸约为120 nm的块体，并对其进行了注量为1.9×1012～7.2×1014 cm －2的快中子（E＞1 MeV）辐照。通过X射线衍射（XRD）分析、扫描电子显微镜与能谱（SEM‐EDS）分析和显微硬度测试研究了快中子辐照对纳米晶Al的微观结构和显微硬度的影响。研究结果表明：快中子辐照同时造成了纳米晶Al的平均晶粒尺寸增大和显微硬度提高。随快中子辐照注量的增大，纳米晶 A l的平均晶粒尺寸和显微硬度分别增大了2.09％～9.09％和3.54％～4.37％。纳米晶A l的平均晶粒尺寸的增长率随快中子注量的增加而增大。