失稳分解法制备双相纳米晶合金

MANUFACTURE OF TWO PHASE NANOSTRUCTURED ALLOY BY SPINODAL DECOMPOSITION

选择ＣｕＮｉＦｅ合金系为研究对象，用光学显微镜和透射电子显微镜对固溶处理和时效组织进行了观察，以探索失稳分解法制备双相纳米晶合金的可行性。其中４８Ｃｕ３０Ｎｉ２２Ｆｅ（摩尔分数，％）的合金成分满足制备双相纳米晶合金的条件：在高温下为单相固溶体，在适当的低温能失稳分解成两相体积分数大致相等的组织，而且这种组织中彼此相隔的两相都可控制在纳米量级。该合金经１１７０℃固溶处理，６００℃时效后可以获得纳米量级的双相组织。该合金的熔点为１１７０～１２００℃，失稳分解的临界点为８５０～９５０℃。

The two phase nanocrystalline alloy by spinodal decomposition in Cu Ni Fe ternary system was investigated using optical microscopy and TEM. If an alloy is single phase at high temperature and at properly low temperature it could spinodally decompose into two phases with equal volume fraction, and the two phases could be controlled in the nanometer region, the alloy could be made into nanometer material by spinodal decomposition. The 48Cu 30Ni 22Fe(mole fraction, %) alloy meets the conditions. The melting point of the alloy is 1 170～1 200 ℃ and the critical temperature of spinodal decomposition is 850～950 ℃. The nano scale two phase microstructure is obtained after 48Cu 30Ni 22Fe(mole fraction, %) alloy was solution treated at 1 170 ℃ for 48 h, water quenched to room temperature and subsequently aged at 600 ℃.