(湖南大學 材料科學與工程學院，長沙 410082)
摘 要: 以直流電弧作為加熱源， 在高純氬氣氛下蒸發(fā)了Ni-Al母合金，制備出粒度小于60 nm的合金納米粉末， 并研究了納米粉末中的相生成規(guī)律。 結(jié)果表明： 納米粉末中合金相的形成規(guī)律與Ni-Al相圖一致； 蒸發(fā)高Ni含量的母合金容易得到以金屬間化合物相ε-AlNi3和δ-AlNi為主的納米粉末；而蒸發(fā)Al含量較高的母合金時， 容易得到γ-Al3Ni2相，且粉末中化合物相的相對含量顯著減少； 改變放電電流的大小可以改變粉末中析出相的種類和相對含量； 而只改變惰性氣體的壓力時， 粉末中的析出相種類不變， 只是相對含量改變。實驗發(fā)現(xiàn)所制備的納米粉末中未出現(xiàn)β-Al3Ni5和Al3Ni低溫相。
關(guān)鍵字: Ni-Al合金； 納米粉末； 合金相； 氣相沉積； 氣相蒸發(fā)
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
