• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2017, Vol. 53 ›› Issue (6): 73-79.doi: 10.3901/JME.2017.06.073

• 材料科学与工程 • 上一篇    下一篇

Ti2AlNb粉末与Ti/Al纳米叠层箔带混合烧结高温微叠层材料的微观结构*

方爽, 熊华平, 程耀永, 林海, 于秋颖, 任新宇, 王淑云   

  1. 北京航空材料研究院焊接与塑性成形研究所 北京 100095
  • 出版日期:2017-03-20 发布日期:2017-03-20
  • 作者简介:方爽,男,1986年出生,博士。主要研究方向为航空新材料塑性成形、粉末冶金及微观组织控制。E-mail:fs107114@126.com熊华平(通信作者),男,1969年出生,博士,研究员,博士研究生导师。主要研究方向为航空材料及结构钎焊扩散焊、焊接材料研制、粉末冶金、增材制造等。E-mail:huaping.xiong@biam.ac.cn;xionghuaping69@sina.cn
  • 基金资助:
    * 航空科学基金资助项目(2014ZF21010); 20161013收到初稿,20170120收到修改稿;

Preparation and Microstructure Characterization of#br# High Temperature Micro-laminated Materials of Ti2AlNb Alloy Powder and Ti/Al Nano-multilayer Foil by Hot-pressed Sintering

FANG Shuang, XIONG Huaping, CHENG Yaoyong, LIN Hai, YU Qiuying, REN Xinyu, WANG Shuyun   

  1. Welding and Plastic Forming Division, Beijing Institute of Aeronautical Materials, Beijing 100095
  • Online:2017-03-20 Published:2017-03-20

摘要:

为了探索研制一种工作温度700~750 ℃,而且室温塑性较好的钛基高温合金,使用Ti/Al纳米叠层箔带和Ti2AlNb合金粉末作为原料,在1 473 K,30 MPa,1.5 h的热压条件下直接混合烧结,制备出新型钛铝系金属间化合物高温微叠层材料(TiAl+Ti2AlNb)样品,其中,Ti/Al纳米叠层箔带在热压烧结过程中的放热反应促进了样品烧结致密化。采用X射线衍射(X-ray diffraction, XRD)、扫描电子显微镜(Scanning electron microscope, SEM)和能谱仪(Energy dispersive spectroscopy, EDS)研究烧结产物相组成及显微结构的影响,并测试微区的显微硬度。结果表明,不同混合方式配比热压烧结体的相组成结构比较相似,烧结体内部主要形成了组织渐变的Ti2AlNb/Ti2Al(Nb)/TiAl显微结构,并且通过XRD也检测到了Ti3Al相。破碎的Ti/Al纳米叠层材料和Ti2AlNb合金粉末在热压烧结后,以扩散反应形成的Ti∶Al∶Nb大约为1∶1∶1的TiAl(Nb)相,其硬度最高(605.85 HV),由Ti/Al纳米叠层箔带生成并保留下来的TiAl相,其硬度最低(251.11 HV)。

关键词: Ti/Al纳米叠层箔带, Ti2AlNb合金, 热压烧结, 显微结构, 硬度, 高温微叠层材料

Abstract:

The aim of this paper is to explore the development of new titanium-based alloy with operating temperature of 700-750 ℃ and with good room temperature plasticity . Fabrication of high temperature micro-laminated Ti-Al intermetallic composites materials (TiAl+Ti2AlNb) by hot-pressed sintering of mixed Ti/Al nano-multilayer foil and Ti2AlNb alloy powder is studied at 1473 K under a pressure of 30 MPa for 1.5 h. The exothermic reaction of Ti/Al nano-multilayer foil during the hot pressing process promotes the densification of the samples. The phase constituent and microstructures of hot-pressed sintering products are subsequently analyzed by X-ray diffraction(XRD), scanning electron microscope(SEM) and energy dispersive spectroscopy(EDS). Additionally the micro-hardness of some typical microzones is also measured. Similarity exists in the phase distribution for the sintering products. Different types of diffusion reactions occurred within the sintered body during hot-pressed sintering, finally leading to the formation of graded microstructures, Ti2AlNb/Ti2Al(Nb)/TiAl. Hot-pressed sintering sample with the Ti2AlNb powder with broken Ti/Al foil shows different hardness in different microzones. The largest hardness (605.85 HV) appears in the reaction formed TiAl(Nb) phase with the Ti∶Al∶Nb ratio of 1∶1∶1, whereas the TiAl phase formed from Ti/Al nano-multilayer material shows the lowest hardness (251.11 HV).

Key words: hardness, hot-press sintering, microstructure, Ti/Al nano-multilayer foil, Ti2AlNb alloy, high temperature micro-laminated materials