Journal of South China University of Technology (Natural Science Edition) ›› 2007, Vol. 35 ›› Issue (12): 71-75.

• Materials Science & Technology • Previous Articles     Next Articles

Sintering Process via Solid-State Reaction of Ti/ AI Composite Powders Prepared by High -Energy Ball Milling

Li Xiao-qiang1  Qu Sheng-guan1  Zhang Zhong-rong2  Shao Ming1  Li Yuan-yuan1   

  1. 1. School of Mechanical Engineering , South China Univ. of Tech. , Guangzhou 510640 , GUaJlgdong , China;2. 061 Base , Chinese Aerospace Science and Tech. Corporation , Kaishan 563108 , Guizhou , China
  • Received:2006-10-16 Online:2007-12-25 Published:2007-12-25
  • Contact: 李小强(1972-) ，男，副教授，主要从事粉末冶金方面的研究. E-mail:Lixq@ scut. edu. cn
  • About author:李小强(1972-) ，男，副教授，主要从事粉末冶金方面的研究.
  • Supported by:

    国家杰出青年科学基金资助项目(50325516) ;国家自然科学基金资助项目(59875015) ;广东省自然科学基金资助项目(05300305 )

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Abstract:

The solid -state diffusion reaction behavior between Ti and Al foils was studied by using optical microscopy and energy spectrometer , and an equation describing the growth of TiA13 phase layer was deduced. Moreover , a two-step solid-state sintering process of milled Ti/ Al composite powders was investigated. The results indicate that ( 1) the proposed two-step solid-state sintering effectively avoids the deformation of powders during the sintering process and helps to obtain dense TiAl alloys with typical microstructure; (2) in order to obtain highly dense TiAl alloy , a sintering at elevated temperature after the presintering for a prolonged time at low temperature is necessaη because the presintering only helps to form thermostable microstructure of TiAl and Ti3Al and the relative density is still low; (3) the high-energy ball milling leads to fine TiAl microstructure , the longer the milling time , the finer the sintered alloy; and (4) with the increase in milling time , the content of lamella colonies in the dual-phase sinter
first increases but then decreases due to non-CIγstallization.

Key words: titanium aluminide, high-energy ball milling, diffusion reaction, solid-state sintering