中国机械工程

• 先进材料加工工程 • 上一篇    下一篇

粉末冶金Ti-22Al-25Nb合金的放电等离子烧结工艺数值模拟与实验研究

贾建波1;刘文超1;刘海亮1;鹿超1;徐岩1,2;杨越1;骆俊廷1   

  1. 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
  • 出版日期:2018-10-10 发布日期:2018-10-08
  • 基金资助:
    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)
    Hebei Provincial Natural Science Foundation of China (No. E2016203157)

Numerical Simulation and Experimental Study on SPS Processes for a Powder Metallurgy Ti-22Al-25Nb Alloy

JIA Jianbo1;LIU Wenchao1;LIU Hailiang1;LU Chao1;XU Yan1,2;YANG Yue1;LUO Junting1   

  1. 1.Education Ministry Key Laboratory of Advanced Forging & Stamping Technology and Science, Yanshan University,Qinhuangdao,Hebei,066004
    2.National Engineering Research Center for Equipment and Technology of C.S.R, Yanshan University,Qinhuangdao,Hebei,066004
  • Online:2018-10-10 Published:2018-10-08
  • Supported by:
    Hebei Provincial Natural Science Foundation of China (No. E2016203157)

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。

关键词: Ti-22Al-25Nb预合金粉末, 放电等离子烧结, 相对密度, 断裂机制

Abstract: 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 numerically 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 sintering 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 experiments to fabricate the Ti-22Al-25Nb alloys. The effects of temperature on the relative density, microstructure evolution and mechanics property of Ti-22Al-25Nb alloy at 50 MPa /10 min were systematically revealed. In addition, the fracture mechanism of the alloys sintered at different temperatures was revealed, 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.

Key words: Ti-22Al-25Nb pre-alloyed powder, spark plasma sintering(SPS), relative density, fracture mechanism

中图分类号: