Phase equilibria in the Co-Ti portion of the Co-Al-Ti ternary system


Phase equilibria of 900, 1000, and 1100 °C in the Co-Ti portion of the Co-Al-Ti system were mainly determined by energy dispersion x-ray spectroscopy. On the Ti-Al side, the β-Ti (A2) phase region is extended by the addition of Co and the β-Ti + AlTi3 (D019) two-phase region appears in the ternary equilibrium, while the AlTi (L10), AlTi3, and β-Ti phases show very low solubility of Co. It was found that the two ternary intermetallic compounds, Co2AlTi (L21) and CoAl2Ti (D8 a ), exist over a wide solubility range along the CoAl(B2)-CoTi (B2) and CoAl3-CoTi3 sections, respectively. The ordering transition and the phase separation due to ordering of the β-Ti, CoAl, or CoTi and Co2AlTi phases fundamentally possessing the bcc structure are also discussed.

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Ishikawa, K., Aoki, K., Himuro, Y. et al. Phase equilibria in the Co-Ti portion of the Co-Al-Ti ternary system. JPE 22, 219 (2001).

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  • Phase Equilibrium
  • Ternary System
  • Isothermal Section
  • 20Al 20Ti
  • Ternary Intermetallic Compound