机械合金化-真空烧结法制备致密细晶钛合金

Fabrication of a High-density Fine-grain P/M Titanium Alloy by Mechanical Alloy and Vacuum Sintering

采用机械合金化-真空烧结方法制备出致密细晶钛合金(Ti-6Al-2Sn-4Zr-6Mo),并研究了球磨时间、烧结温度等制备条件对烧结材料密度和显微组织的影响规律。结果表明,随着球磨时间的增加,钛合金烧结材料的密度逐渐升高,显微组织从初生α相+针状的转变β组织逐步转化为细等轴状的α+β组织,并且其晶粒尺寸逐渐减小。当球磨时间为40h,烧结温度为1200℃时,烧结材料的相对密度达到99.1%,平均晶粒尺寸仅为2μm。

A high-density fine-grain P/M titanium alloy of Ti-6Al-2Sn-4Zr-6Mo was prepared by mechanical alloying and vacuum sintering process. Effects of ball-milling time and sintering temperature on density and microstructure of the P/M titanium alloy have been investigated. The experimental observation shows that with increasing in ball-milling time, the density of Ti alloy is increased and its microstructure is converted from primary α phase and needle-like β phase into fine equiaxed α+β phase, in which the grain size is decreased gradually. The relative density of sintered materials with average grain size of only 2 μm reaches 99.1% with ball-milling time of 40 h and sintering at 1 200 ℃.