置氢TC4钛合金粉末热等静压制件组织与性能研究

Structure and Properties of Sintering Body by Hot Isostatic Pressing Utilizing TC4 Hydrogenated Powder

采用置氢钛合金粉末热等静压成形与钛合金热氢处理技术相结合的新工艺路线制备合金,研究了置氢量及热等静压工艺参数对置氢TC4合金粉末热等静压制件组织性能的影响规律。结果表明:随着置氢量的增加,置氢TC4合金粉末热等静压后制件的密度呈逐渐增高的趋势;热等静压制件的片层状组织尺寸变薄、针状的组织变细,等轴颗粒组织愈来愈多;退火后制件的显微组织中等轴状的颗粒增多,压缩屈服强度和抗压强度均逐渐增大;热等静压制件与粉末原料的氢含量及相组成基本相近,真空退火除氢后氢含量则达到了安全使用水平,置氢量0.42%TC4合金粉末热等静压制件致密效果好、综合力学性能高。

The effect of hydrogen content and processing parameters on structure and properties of TC4 alloy was researched by means of a new method to produce titanium alloy of combining hot isostatic pressing using hydrogenated powder and technology of hydrogen treatment for titanium alloy. The results show that with increasing of hydrogen content, the density of TC4 titanium sintered body gradu- ally increases and the sheet microstructure gets thinner and finer and the grain size becomes smaller and isometric. After annealing, with hydrogen content increasing, the isometric grain of the TC4 titanium product increases, the compression yield limit and strength shows a gradually rising trend. The hydrogen content and the phase composition of the product by hot isostatic pressing are basically close to powder stock, and the safety status of hydrogen content of the product after annealing corresponding to the TC4 alloy state is achieved. The density and mechanical property of the TC4 titanium alloy are the best with the hydrogen mass fraction of 0.42% .