粉末粒度偏析对Ti-5Al-2.5Sn ELI粉末合金拉伸性能的影响  

Effects of powder size segregation on tensile properties of Ti-5Al-2.5Sn ELI alloy powder

作　　者：程文祥[1] 徐磊[1] 雷家峰[1] 刘羽寅[1] 杨锐[1] 

机构地区：[1]中国科学院金属研究所,沈阳110016

出　　处：《中国有色金属学报》2013年第2期362-369,共8页The Chinese Journal of Nonferrous Metals

摘　　要：采用无坩埚感应熔炼超声气体雾化法制备洁净的Ti-5Al-2.5Sn ELI预合金粉末,用热等静压包套技术制备全致密的Ti-5Al-2.5Sn ELI粉末合金。采用常规工艺填充5种不同粒度分布的Ti-5Al-2.5Sn ELI粉末样品并进行热等静压处理,得到全致密的粉末合金;并采用长时间振实工艺填充一组粉末冶金样品。结果表明:以常规工艺填充的粉末样品制得的5组粉末合金压坯的气体含量处于同一水平,晶粒尺寸最大差异在10μm左右,合金的室温和低温拉伸性能无明显差异。长时间振实工艺填充粉末会引起大颗粒粉末聚集于包套上部、细小颗粒粉末则向下沉降的粒度偏析现象,该现象对粉末合金的室温性能无明显影响,但造成包套端部合金样品的低温塑性显著下降,下降幅度达50%。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 pan; 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.

关 键 词：Ti-5Al-2 5SnELI粉末 热等静压 粒度偏析 拉伸性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]