摘要
选用Ti-22Al-25Nb预合金粉末为实验初始原料,采用放电等离子烧结工艺(SPS)制备组织致密的粉末冶金Ti-22Al-25Nb合金。采用MSC.Marc有限元软件对SPS过程中粉末的致密化过程进行了数值模拟,分析了烧结温度、保温时间和烧结压力对粉末致密化过程的影响,揭示了粉末相对密度随烧结温度、保温时间和烧结压力的变化规律。根据模拟结果,在950~1 200℃温度区间、50 MPa烧结压力和10~20 min保温时间的条件下,完成系列SPS烧结实验,制备获得Ti-22Al-25Nb合金。系统分析了50 MPa/10 min烧结条件下温度对Ti-22Al-25Nb合金的相对密度、显微组织和力学性能的影响,揭示了烧结合金的断裂机制。实验结果表明烧结合金在950℃/50 MPa/10 min条件下具有最优的综合力学性能,延伸率和屈服强度分别达到8.14%和691.04 MPa。
A Ti-22Al-25Nb alloy with dense microstructure was prepared by using SPS method from pre-alloy powders.The densification of the powders during the SPS processes was simulated nu-merically by using the finite element software MSC.Marc.The effects of sintering temperature,holding time and sintering pressure on the densification processes of the Ti-22Al-25Nb powders were analyzed,respectively.The evolutions of relative density varying with sintering temperature,holding time and sin-tering pressure were revealed,respectively.Based on the results of simulation,the temperature range of 950~1 200℃,50 MPa pressure and 10~20 min holding time were utilized in a series of sintering experi-ments to fabricate the Ti-22Al-25Nb alloys.The effects of temperature on the relative density,micro-structure evolution and mechanics property of Ti-22Al-25Nb alloy at 50 MPa/10 min were systemati-cally revealed.In addition,the fracture mechanism of the alloys sintered at different temperatures was re-vealed,respectively.The results show that the alloys sintered at 950℃/50 MPa/10 min exhibit a better mechanics property with the elongation of 8.14%and the yield stress of 691.04 MPa.
作者
贾建波
刘文超
刘海亮
鹿超
徐岩
杨越
骆俊廷
JIA Jianbo;LIU Wenchao;LIU Hailiang;LU Chao;XU Yan;YANG Yue;LUO Junting(Education Ministry Key Laboratory of Advanced Forging&Stamping Technology and Science,Yanshan University,Qinhuangdao,Hebei,066004;National Engineering Research Center for Equipment and Technology of C.S.R,Yanshan University,Qinhuangdao,Hebei,066004)
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2018年第19期2377-2383,共7页
China Mechanical Engineering
基金
河北省自然科学基金资助项目(E2016203157)
秦皇岛市科学与技术基金资助项目(E201602A008)
燕山大学博士基金资助项目(B936)
作者简介
贾建波,男,1981年生,副教授、博士。研究方向为难变形合金塑性加工。发表论文30余篇。E-mail:jianbojia@ysu.edu.cn;(通信作者)徐岩,女,1983年生。燕山大学机械工程学院副教授、博士。研究方向为难变形合金塑性加工。发表论文30余篇。E-mail:xuyan_916@ysu.edu.cn。
