机械合金化Mg-LaNi_5合金的研究

Study on the Mg-LaNi_5 alloy prepared by mechanical alloying

采用X射线衍射(XRD)、扫描电子显微镜(SEM )、差热分析(DTA)等测试方法研究了新型材料Mg 6 9%LaNi5(质量分数)的组织形貌及热稳定性能等。结果表明:该合金在转速为2 80r/min的条件下球磨2 5 0h后形成了短程有序或无序的镧、镁、镍等非晶及MgNi2 纳米晶(3nm)组织;所得样品的颗粒形状主要为规则的球形或近球形,还有少量多角形等不规则形状。球磨样品在76 3K温度下保温35d ,得到热稳定性较好的具有纳米尺度(2 5nm)的Mg2 NiLa ,Mg2 Ni,MgNi2 三相合金。

The microstructure and the thermal stability of the novel Mg-69wt% LaNi5 alloy were studied by X-ray diffraction (XRD), scanning electron microscope (SEM), differential thermal analysis (DTA). The results show that the amorphous structure and nanocrystalline of the Mg-69wt% LaNi5 alloy can be obtained after mechanical alloying for 250 hours at 280 r/min, and the shape of the particles mostly are spheroidal. Heat treated for 35 days at 763 k, the novel Mg-69wt% LaNi5 alloy is stable and consists of Mg2NiLa, Mg2Ni, MgNi2 phases with the average grain size of 25 nm.