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利用高能球磨机对不同 Ｃｒ含量的 Ｎｉ５０－Ａｌ５０－ｘ－Ｃｒｘ（ｘ＝５， １０， １５， ２０， ２５）粉末进行机械合金化采用 ＸＲＤ，ＳＥＭ； ＴＥＭ和 ＤＴＡ等手段系统研究了合金元素 Ｃｒ替代 Ａｌ后对 ＮｉＡｌ机械合金化过程及产物的影响结果表明，高能球磨显著扩大了 Ｃｒ在β－ＮｉＡｌ中的固溶度， Ｃｒ含量的增加使反应机制发生变化，得到逐渐趋于无序的 ＮｉＡｌ（Ｃｒ）化合物。Ｎｉ５０Ａ１５０－ｘＣｒＸ（ｘ＝５，１０，１５）三种粉末球磨终产物具有较好的组织稳定性，加热至１０００℃仍未发生相分解，均保持β－ＮｉＡｌ（Ｃｒ）结构；而 Ｎｉ５０－Ａｌ３０－Ｃｒ２０和 Ｎｉ５０－Ａｌ２５－Ｃｒ２５两种球磨产物在高温下发生分解，形成β相、 γ’相和。α－Ｃｒ多相组织
The mechanical alloying of Ni50-Al50-x-Crx (x = 5, 10, 15, 20, 25) powders with different Cr content by high energy ball mill was studied systematically by means of XRD, SEM, TEM and DTA. Al after NiAl mechanical alloying process and product results show that high energy ball milling significantly expands the solid solubility of Cr in the β-NiAl, Cr content of the reaction mechanism changes, get gradually unordered NiAl ( Cr) compound. The final product of Ni50A150-xCrX (x = 5,10,15) powders had good microstructure stability and maintained the β-NiAl (Cr) structure when heated to 1000 ℃. However, Ni50-Al30 Cr20 and Ni50-Al25-Cr25 two ball milling products decompose at high temperature to form β phase, γ ’phase and. α-Cr multiphase tissue