Co含量对Ni-Al机械合金化的影响

Effect Cobalt Amounts on Mechanical Alloying of Ni Al

Ｃｏ元素的加入对ＮｉＡｌ合金的机械合金化过程及产物有很大影响·Ｃｏ含量变化使反应机制发生明显改变，并同时得到不同的反应产物·Ｃｏ含量为５％（原子分数）时，反应机制仍属于爆炸式反应，粉末颗粒较细且均匀；但１０％（原子分数）Ｃｏ元素的加入抑制了ＮｉＡｌ化合物爆炸式反应生成，并导致类“非晶”相的生成；而Ｃｏ含量为２０％（原子分数）时，导致了γＮｉ（Ａｌ，Ｃｏ）过饱和固溶体的形成·粉末颗粒最大，均匀性较差·

Adding Co element has a great effect on its mechanical alloying process and the final products. Different of Co makes reaction mechanism vary distinctly,meanwhile obtaining the different reaction products. When Co amounts to 5%, reaction mechanism still belongs to explosive reaction. Powder particles are fine and uniform. 10%Co restrains the explosive reaction, resulting in “armorphous like” phase formation. TEM observation shows fine crystalline grain NiAl compound exits. But 20%Co results in forming γ Ni(Al,Co) super saturation solid solution. The powder particles are large and bad uniform.