【摘要】 系统研究了两个等电子浓度线(e/a=1.20,1.25)上Ti-Zr-Ni铸态合金的组织与结构,发现吸铸法可在很宽的成分区间(TixZr100-x)100-yNiy,43.75％≤x≤81.25％,17％≤y≤20％)内获得Ti-Zr-Ni准晶,其中,Ti40Zr40Ni20为理想准晶成分,能形成长15 mm、直径6 mm的单相准晶棒.准晶成分特征研究表明: Ti-Zr-Ni准晶系也具有与Al基三元准晶系相似的相图特征.一方面, Ti-Zr-Ni准晶与其类似相一起构成准晶“等电子浓度线”现象;同时,三元准晶成分满足准晶“变电子浓度线”特征,形成准晶的理想成分Ti40Zr40Ni20位于准晶等电子浓度线与变电子浓度线交点处.更多还原

【Abstract】 Ti-Zr-Ni alloy rods along two e/a-constant lines (e/a=1.20, 1.25) were prepared by using suction-casting method, the systematic investigation on these as-cast alloys shows that Ti-Zr-Ni quasicrystals are formed over a large range of composition, (TixZr100-x)100-yNiy (43.75%≤ x ≤81.25%, 17%≤ y ≤20%). Among them, Ti40Zr40Ni20 is the ideal quasicrystals-forming composition, where a nearly pure bulk quasicrystal rod, 6 mm in diameter and 15 mm in length, can be obtained. The Ti-Zr-Ni system are found to have the similar characteristic to the Al-base ternary quasicrystalline phase diagram features, indicating that the ideal quasicrystals-forming composition should be located at the crossing point of the two specific lines, termed as e/a-constant and e/a-variant lines. This kind of phase diagram features can be used as an empirical criterion forming ternary quasicrystals.更多还原