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(Ti-50%(原子分数)Al)-10%Al2O3粉体经过球磨的机械活化(MA)后,用放电等离子烧结(SPS)工艺,在烧结的同时进行固化。采用机械活化-放电等离子烧结(MA-SPS)的方法原位烧结制备Ti Al-Al2O3块体纳米材料。球磨前后,(Ti-50%(原子分数)Al)-10%Al2O3粉体的衍射图(XRD)相似。MA后得到晶粒度<25nm的纳米粉体,其中Al2O3起到机械活化和细化晶粒的作用,促使粉体快速纳米化。纳米粉体在温度低于800℃、烧结时间<5min的烧结参数下,烧结成Ti Al纳米合金。Ti Al纳米合金的微观结构表明,合金有γ-Ti Al和α2-Ti3Al双相组织。SPS原位烧结后,得到密度为3.73g/cm3的(γ+α2)双相组织,组成相的晶粒度<130nm。
(Ti-50% (atomic fraction) Al) -10% Al2O3 powder is subjected to mechanical activation (MA) after ball milling and then is subjected to SPS by sintering while being cured. TiAl-Al2O3 bulk nanostructured materials were prepared by in-situ sintering by mechanical activation-discharge plasma sintering (MA-SPS). Before and after ball milling, the diffraction pattern (XRD) of (Ti-50% (Al fraction) Al) -10% Al2O3 powder is similar. After MA to obtain the grain size of <25nm nanopowder, Al2O3 which play a mechanical activation and grain refinement, prompting the rapid nano-powder. Under the sintering temperature of less than 800 ℃ and sintering time <5min, the nanometer powder is sintered into TiAl nano-alloy. The microstructure of TiAl nano-alloy shows that the alloy has γ-TiAl and α2-Ti3Al dual phase structure. SPS in situ sintering, to obtain a density of 3.73g / cm3 (γ + α2) dual phase structure, the grain size of the composition phase <130nm.