(湖南大学 材料科学与工程学院，长沙 410082)
摘 要: 以直流电弧作为加热源， 在高纯氩气氛下蒸发了Ni-Al母合金，制备出粒度小于60 nm的合金纳米粉末， 并研究了纳米粉末中的相生成规律。 结果表明： 纳米粉末中合金相的形成规律与Ni-Al相图一致； 蒸发高Ni含量的母合金容易得到以金属间化合物相ε-AlNi3和δ-AlNi为主的纳米粉末；而蒸发Al含量较高的母合金时， 容易得到γ-Al3Ni2相，且粉末中化合物相的相对含量显著减少； 改变放电电流的大小可以改变粉末中析出相的种类和相对含量； 而只改变惰性气体的压力时， 粉末中的析出相种类不变， 只是相对含量改变。实验发现所制备的纳米粉末中未出现β-Al3Ni5和Al3Ni低温相。
关键字: Ni-Al合金； 纳米粉末； 合金相； 气相沉积； 气相蒸发
nano powders prepared by vapor deposition
（ School of Materials Science and Engineering,
Hunan University, Changsha 410082, China）
Abstract: Ni-Al alloy nanometer powders were prepared by vapor deposition technology with arc as evaporation source. The mean particle sizes of the obtained powders were less than 60 nm. The formation regularities of phases in the as-prepared powders were investigated. The results show that the regularities are consistent with Ni-Al phase diagram. The intermetallic compound phases of ε-AlNi3 and δ-AlNi are easily to form in the nanometer powders when master alloys rich in Ni are evaporated. On the other hand, when master alloys rich in Al are evaporated, γ-Al3Ni2 is easy to form in the nanometer powders, and the relative amount of compound phases decreases obviously. The phases in the nanometer powders and its relative amount change with arc current, but changing Ar gas pressure can only influence the relative amount of phases. The low temperature phases of β-Al3Ni5 and Al3Ni do not form in the nanometer powders.
Key words: Ni-Al alloy； nanometer powder； alloy phase； PVD； gas evaporation
