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采用 Ｘ射线衍射、初始交流磁性率和差热分析研究了机械合金化 Ｎｄ－１１Ｆｅ－Ｔｉ（原子比）合金粉和机械研磨 ＮｄＦｅ_１１Ｔｉ比台物粉在退火过程中的相转变．球磨７ｈ后二者均由非晶相和Ｔｉ在α－Ｆｅ中过饱和固溶体组成。机械合金化粉末样品中的非晶相的晶化温度为 ６２０℃，晶化亚稳相为 ＴｂＣｕ_７，结构的 Ｎｄ（Ｆｅ；Ｔｉ）７， ９００℃以上退火时。亚稳相转变成 ＴｈＭｎ１２结构 Ｎｄ（Ｆｅ， Ｔｉ）１２相；机械研磨的ＮｄＦｅ１１Ｔｉ化合物树中非晶相在６３８℃晶化形成的Ｎｄ（Ｆｅ，Ｔｉ）７在１０００℃以上退火向Ｎｄ（Ｆｅ，Ｔｉ）_１２相转变。这些差别归因于两种样品中Ｔｉ原子在非晶相与α—Ｆｅ相中分配的不同
The phase transformation of the mechanically alloyed Nd-11Fe-Ti (atomic ratio) alloy powder and the mechanically-ground NdFe_ (11Ti) material over the annealing process was investigated by X-ray diffraction, initial AC magnetic susceptibility and differential thermal analysis. After milling for 7h, both of them were composed of amorphous phase and supersaturated solid solution of Ti in α-Fe. The crystallization temperature of the amorphous phase in the mechanically alloyed powder sample is 620 ° C, the crystallized metastable phase is TbCu_7, and the structure of Nd (Fe; Ti) 7 anneals above 900 ° C. (Fe, Ti) 12 phase of the ThMn12 structure. Nd (Fe, Ti) 7 crystallized from the amorphous phase of the mechanically pulverized NdFe11Ti compound annealed at 638 ℃ annealed above 1000 ℃ to Nd (Fe, Ti) _12 phase transition. These differences are attributed to the difference in the distribution of Ti atoms between the amorphous and α-Fe phases in both samples