Grain Refinement in α+β-type Ti-4.5Al-6Nb-2Fe-2Mo Alloys through Precipita-tion of TiB or Rare Earth Oxides
The β-grain growth in biomedical α+β-type Ti-4. 5Al-6Nb-2Fe-2Mo (mass％) alloys with the addition of small amounts of rare earth metals such as La, Y, Ce, and Er and boron was investigated in the β region of the alloys at temperatures of 1173-1573 K. The addition of Er (0. lmass％),La (0. 01mass％),and Y (0. lmass％) suppressed the β-grain coarsening up to heating temperatures of 1273,1373,and 1473 K, respectively; however, this effective suppression of grain growth was not observed in the Ce-added (0. lmass％) alloy. The marked β-grain refinement in the Y-added alloy appears to be caused by the relatively high stability of theY2O3 precipitate at high temperatures compared with other rare earth metal oxides. The addition of 0. 003-0. 03mass％ boron was effective in suppressing the β-grain growth, where the effectiveness depended on the content of boron. An increase in the boron content extended the effective temperature range for ff-grain growth suppression. The TiB precipitates were rod-shaped elongated along the forging direction in the β matrix or small round-shaped.
α-β-type titanium (Ti) alloy rare earth oxide TiB β-processing grain growth
Yasunori Kimura Nobuyuki Umetsu Naomichi Iwata Shinichiro Nakaoka Kyosuke Ueda Takayuki Narushima
Department of Materials Processing,Tohoku University,Sendai 980-8579,Japan
国际会议
The 12th World Conference Titanium(第十二届世界钛会 Ti-2011)
北京
英文
2077-2080
2011-06-19（万方平台首次上网日期，不代表论文的发表时间）