放电等离子烧结制备Ti-22Al-25Nb合金及致密化机理  

Preparation and densification mechanism of Ti-22Al-25Nb alloy prepared by spark plasma sintering

作　　者：贾建波[1] 杨越[1] 孙威 仲晓晓 徐岩[1,2] 顾勇飞 骆俊廷[1] JIA Jian-bo;YANG Yue;SUN Wei;ZHONG Xiao-xiao;XU Yan;GU Yong-fei;LUO Jun-ting(Education Ministry Key Laboratory of Advanced Forging and Stamping Technology and Science,Yanshan University,Qinhuangdao 066004;National Engineering Research Center for Equipment and Technology of C.S.R,Yanshan University,Qinhuangdao 066004,China)

机构地区：[1]燕山大学先进锻压成形技术与科学教育部重点实验室,秦皇岛066004 [2]燕山大学国家冷轧板带装备及工艺工程技术研究中心,秦皇岛066004

出　　处：《中国有色金属学报》2019年第7期1399-1407,共9页The Chinese Journal of Nonferrous Metals

基　　金：河北省自然科学基金资助项目(E2016203157);国家自然科学基金资助项目(51875502)~~

摘　　要：以Ti-22Al-25Nb(摩尔分数,%)预合金粉末为实验初始原料,采用放电等离子烧结工艺(SPS)方法,在温度为950~1200℃,保温时间为10~20min,压力为35~80MPa的条件下制备晶粒小、组织致密的粉末冶金Ti-22Al-25Nb合金。研究烧结温度、烧结压力和保温时间对预合金粉末致密化过程的影响,分析粉末的烧结致密化机理,揭示烧结温度、烧结压力和保温时间对Ti-22Al-25Nb烧结合金的相对密度、相组成、显微组织以及力学性能的影响规律,明确烧结合金的室温断裂机制。结果表明:经950℃、80MPa、10min烧结的Ti-22Al-25Nb合金相对密度达到99.43%,具有更优异的综合力学性能,其室温伸长率、屈服强度和抗拉强度分别达到9.38%、933.57MPa和990.01MPa。Ti-22Al-25Nb (mole fraction,%) pre-alloyed powders were used as the experimental starting materials.A powdery metallurgy Ti-22Al-25Nb alloy with fine grain size and dense microstructure was prepared using the spark plasma sintering process (SPS) method at the temperature of 950 1200 ℃,holding time of 10 20 min and pressure of 35 80 MPa.The effects of sintering temperature,sintering pressure and holding time on the densification of pre-alloyed powders were studied.The sintering densification mechanism was analyzed.The influences of sintering temperature,sintering pressure and holding time on the relative density,phase composition,microstructure and mechanical properties of the sintered Ti-22Al-25Nb alloy were revealed.In addition,the room temperature fracture mechanism of the sintered alloy was clarified.The results show that the relative density of the Ti-22Al-25Nb sintered alloy at (950 ℃,80 MPa,10 min) reaches 99.43%,and it has better comprehensive mechanical properties.The room temperature elongation,yield strength and tensile strength reach 9.38%,933.57 MPa and 990.01 MPa,respectively.

关 键 词：TI-22AL-25NB合金 放电等离子烧结 致密化 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]