粉末注射成形TiAl超固相线液相烧结工艺研究

Supersolidus liquid phase sintering process for injection molded TiAl

以Ti-47．5％Al-2．5％V-1．0％Cr（原子数分数）气雾化预合金粉末为原料，采用粉末注射成形工艺制备了TiAl合金材料，重点研究了该TiAl合金超固相线液相烧结温度区间和保温时间以及烧结体显微组织、密度和压缩性能的变化规律。结果表明：烧结温度在1410～1450＊℃，保温时间在1h以内，烧结体可以致密化；在1450℃保温30min，烧结体相对密度可以达到95％，烧结体的抗压强度为2105MPa，压缩率达到30．9％，接近铸态合金力学性能；随烧结温度升高，烧结体近片层组织中的7等轴晶逐渐减少，片层团逐渐增加。

This paper is dealing with an injection molding of gas atomized pre-alloy powders of Ti- 47.5Al- 2.5V- 1.0Cr. The sintering temperature range, sintering time and the effects of sintering temperature on microstructure, density and compressive property of the alloy of supersolidus liquid phase sintering were investigated. Results Show that the specimens can be densified rapidly at 1 410 - 1 450℃ for 60 min. When vacuum sintering is employed, a near full density of 95% is obtained at 1 450℃ after 30 min holding, the compression strength and compression ratio are 2 105MPa and 30.9% respectively, which is close to that of cast alloy. With sintering temperature increasing, the amount of γ phase decreases gradually and the amount of lamellar phase increases guadually.