机械合金化制备Ni-Al-Fe-Nb粉体

Ni-Al-Fe-Nb Powders Preparated by Mechanicalalloyin

研究球磨Ni-30 mol%Al-14 mol%Fe-2 mol%Nb混合粉末过程中组织形态特征及微观结构的变化规律。采用QM-ISP2行星式球磨机经451 r/min进行高能球磨30 h。结果表明:粉末X射线衍射图谱的宽度和强度均随着球磨时间的延长逐渐加宽和降低,这是晶粒细化和晶格畸变共同作用的结果。随着机械合金化的进行,粉末的晶粒度逐渐减小,而晶格常数和畸变则不断增加。粉末Ni-30 mol%Al-mol%Fe-2mol%Nb混合物球磨5 h即开始合金化,但仍然基本保持原来的结构;球磨至10 h时,样品中Al相几乎完全消失,大部分Fe原子从原来的bcc结构转变为fcc结构,球磨时间为30 h时,Fe,Al,Nb相互合金化,样品为均匀的固溶体。所得粉末大多数为规则的近球形或球形,所得复合粉末热稳定性良好。

The characteristics of morphologies and changes of the microstructures in mechanically alloyed Ni - 30mol% Al - 14mol% Fe - 2mol% Nb mixed powder were investigated. We uses QM - ISP2 planet type ball mill to carry on the high - energy ball grinding for 30 hours. The results showed that the width and intensity of X - ray diffraction spectrum increased with ball milling time, which was caused by the reduction of crystal size and the increase of microstrain. With the prolongation of milling time, the crystal size of mixed the powder reduced,while its lattice constant and lattice distortion increased gradually. Powder Ni - 30mol% Al - 14mol% Fe - 2mol% Nb mixture ball ground for 5h namely starts to alloy, but it still maintained the original structure. When ball ground for10h ,Al in the sample nearly vanished, the majority of Fe atoms transformed from the original bee structure to fee structure. When ball grinding time is 30h, Fe, Al, Nb mutually alloyed, and the sample became even solid solution. The obtained powders looks like near sphere or sphere, and .the thermostahility of the obtained compound powder is good.