(中國科學(xué)院 金屬研究所，沈陽110016)
摘 要: 采用無坩堝感應(yīng)熔煉超聲氣體霧化法制備潔凈的Ti-5Al-2.5Sn ELI預(yù)合金粉末，用熱等靜壓包套技術(shù)制備全致密的Ti-5Al-2.5Sn ELI粉末合金。采用常規(guī)工藝填充5種不同粒度分布的Ti-5Al-2.5Sn ELI粉末樣品并進(jìn)行熱等靜壓處理，得到全致密的粉末合金；并采用長時(shí)間振實(shí)工藝填充一組粉末冶金樣品。結(jié)果表明：以常規(guī)工藝填充的粉末樣品制得的5組粉末合金壓坯的氣體含量處于同一水平，晶粒尺寸最大差異在10 μm左右，合金的室溫和低溫拉伸性能無明顯差異。長時(shí)間振實(shí)工藝填充粉末會(huì)引起大顆粒粉末聚集于包套上部、細(xì)小顆粒粉末則向下沉降的粒度偏析現(xiàn)象，該現(xiàn)象對粉末合金的室溫性能無明顯影響，但造成包套端部合金樣品的低溫塑性顯著下降，下降幅度達(dá)50%。
關(guān)鍵字: Ti-5Al-2.5Sn ELI粉末；熱等靜壓；粒度偏析；拉伸性能
（Institute of Metal Research, Chinese Academy of Sciences, Shenyang110016, China）
Abstract:Ti-5Al-2.5Sn ELI pre-alloyed powders were prepared by electrode induction melting gas atomization process, and Ti-5Al-2.5Sn ELI alloy was prepared through hot isostatic pressing route. Five different HIPed preforms of Ti-5Al-2.5Sn ELI alloy were prepared. Five HIPed performs were prepared by the same hot isostatic pressing, powder filling and taping parameters except various original powder size distribution ranges. Powder size segregation usually occurred during powder filling and long-time taping and its influence on alloy properties were both studied. The results show that, in the first group of HIPed preforms prepared by typical powder filling and taping parameters, the air contents of the five preforms are almost the same, while the largest grain size difference is about 10 μm; no obvious difference is found on tensile properties of different samples. While in HIPed preforms prepared by long-time taping and powder filling process, cryogenic tensile properties of samples from the top of the capsule deteriorate significantly due to powder size segregation phenomenon.
Key words: Ti-5Al-2.5Sn ELI powder; hot isostatic pressing; powder size segregation; tensile properties
