纳米晶Ti-Fe-Ni合金机械合金化的研究

Investigation of the Nanocrystalline Ti Fe Ni Alloy Synthesized by Mechanical Alloying

应用ＸＲＤ，ＴＥＭ，ＤＳＣ等实验方法研究了第三组元Ｎｉ对Ｆｅ－Ｔｉ二元混合元素粉机械合金化反应的影响．试验中原子数百分比分别以５％和１５％Ｎｉ取代部分Ｆｅ元素．研究结果表明固态合金化合成晶粒尺寸分别为１２ｎｍ和６ｎｍ的纳米晶Ｂ２相．合金化中经历球磨“退火”过程，微观点阵畸变逐渐减弱，晶粒长大．Ｎｉ元素能使合成的Ｂ２结构纳米晶ＴｉＦｅ相的点阵畸变减小．合成的纳米晶相在９７３Ｋ产生相分解。

By means of XRD, TEM and DSC, the influence of Ni on the mechanical alloying of nanocrystalline TiFe alloy is investigated. 5% and 15% Ni are substituted for Fe in mechanical alloying.The results show that the nanocrystalline B 2 phases with grain size 6nm and 12 nm are synthesized by mechanical alloying. The synthesized B 2 phase undergoes an“annealling”process during further milling, The lattice distortion is decreased and the grain grown. The synthesized nanocrystalline phase is discomposed at 973 K,and a martensitic phase TiNi phase is formed.