【摘要】 本文为了探明Al-Cu-Cr系准晶及其类似相的形成规律,以指导Al-Cu-Cr系准晶合金设计。通过分析研究用热压法制备的Al-Cu-Cr准晶与纯铝的复合材料中不同条件下形成的各个Al-Cu-Cr相的成分和结构,绘制了Al-Cu-Cr三元成份-结构相图,结果表明相图中存在两条等电子浓度线,一条是二十面体准晶及其类似相的等电子浓度线,电子浓度e/a=1.86;另一条是十次准晶及其类似相的等电子浓度线,电子浓度e/a=2.09。这充分证实了准晶及其类似相是电子相,服从Hume-Rothery规则。更多还原

【Abstract】 In order to understand the formation regulation of Quasicrystals and Approximants in Al-Cu-Cr and guide the alloy design of Al-Cu-Cr quasicrystals,The composition and microstructure of Al-Cu-Cr phases formed in the Al-Cu-Cr qusicrystals/Al composites synthesized by hot-pressing were analyzed using electron probe,transmission electron microscope,scanning electron microscope and x-ray diffraction.The results show there are double e/a-constant line in the Al-Cu-Cr concentration diagram.The iconsahadral quasicrystals and its approximants exist on or near to a line at constant electron per atom e/a=1.86,the dacagonal quasicrystals and its approximants exist on or near to a line at e/a=2.09.The Fermi sphere in these phases nearly touches their respective pseudo-Brillouin zones defined by the intense diffraction spots,thus these quasicrystais and approximants are Hume-Rothery phases.更多还原