CAJ | 학술논문

研究了不同球磨时间内Ti-Al复合粉末显微结构及成分的演变.随着球磨时间的延长,原始粉末的形貌发生了一系列变化,从球磨2h的扁平状变为球磨6h的细小的等轴状.球磨8h后粉末的晶粒尺寸达到纳米级,平均约为17nm.对钛铝复合粉末的演化机理进行了分析.在球磨过程中,铝逐渐融入钛晶格形成钛的固溶体.球磨不同时间的粉末中钛铝反应的起始温度的差热分析表明,机械合金化细化了复合粉末,显著降低了钛、铝反应的起始温度.
연구료불동구마시간내Ti-Al복합분말현미결구급성분적연변.수착구마시간적연장,원시분말적형모발생료일계렬변화,종구마2h적편평상변위구마6h적세소적등축상.구마8h후분말적정립척촌체도납미급,평균약위17nm.대태려복합분말적연화궤리진행료분석.재구마과정중,려축점융입태정격형성태적고용체.구마불동시간적분말중태려반응적기시온도적차열분석표명,궤계합금화세화료복합분말,현저강저료태、려반응적기시온도.
The evolution in microstructure and composition of the milled Ti-Al composite powder with different milling time were investigated.It shows that with the milling time increasing,the initial powder underwent a successive change in its morphology from a flattened shape (2 h) to a fine,equiaxed and uniform one (above 6 h).The milled Ti-Al composite powder was nanocrystalline with the average crystallite size of about 17 nm after milling for 8 h.The evolution mechanism of Ti-Al composite powder was elucidated.The Ti(Al) solid solution is formed through a gradual and progressive solution of Al into Ti lattice.By differential thermal analysis on the ignition temperature of the reaction between Ti and Al as a function of milling time,it indicates that mechanical milling of the powders significantly lowered the ignition temperature of the reaction by refining its Ti-Al composite structure.