TY - JOUR
T1 - Phase equilibria in Ir-rich portion of Ir-Al-X (X
T2 - V, Nb and Ta) ternary systems
AU - Miura, Seiji
AU - Ohkubo, Kenji
AU - Terada, Yoshihiro
AU - Kimura, Yoshisato
AU - Mishima, Yoshinao
AU - Yamabe-Mitarai, Yoko
AU - Harada, Hiroshi
AU - Mohri, Tetsuo
N1 - Funding Information:
The authors wish to acknowledge the technical assistance of Mr. N. Miyazaki of Hokkaido University. Present study is partially supported by grant-in-aid for encouragement of young scientists from the Ministry of Education, Science, Sports and Culture, Japan, no. 09875163.
PY - 2005/5/31
Y1 - 2005/5/31
N2 - Isotherms of the Ir-rich portion of the Ir-Al-X (X: V, Nb, Ta) systems composed of fcc-Ir solid solution ((Ir)ss), Ir-based L12 intermetallic compounds Ir3X and B2-IrAl are presented as a second report of a series of investigations on the phase equilibria in the (Ir or Rh)-Al-X (X: Ti, Zr and Hf, or, V, Nb and Ta) ternary systems. In both Ir-Al-Nb and Ir-Al-Ta systems fcc/L12/B2 three-phase equilibrium is found. In Ir-Al-V system, Ir solid solution and Ir3V have close compositions each other and fcc/L12/B2 three-phase equilibrium is expected. No ternary compound is observed in all of the isotherms. Solid solubility of each phase is confirmed by chemical analysis by wavelength dispersive X-ray spectroscopy (WDS). The direction of the solubility lobe of L1 2-Ir3X with Al addition is explained in terms of the nearest neighbor interactions. Liquidus surfaces are also established by taking into account the microstructure of as-cast alloys, differential thermal analysis (DTA) data, and the Ir-Al and the Ir-X binary phase diagrams reported previously.
AB - Isotherms of the Ir-rich portion of the Ir-Al-X (X: V, Nb, Ta) systems composed of fcc-Ir solid solution ((Ir)ss), Ir-based L12 intermetallic compounds Ir3X and B2-IrAl are presented as a second report of a series of investigations on the phase equilibria in the (Ir or Rh)-Al-X (X: Ti, Zr and Hf, or, V, Nb and Ta) ternary systems. In both Ir-Al-Nb and Ir-Al-Ta systems fcc/L12/B2 three-phase equilibrium is found. In Ir-Al-V system, Ir solid solution and Ir3V have close compositions each other and fcc/L12/B2 three-phase equilibrium is expected. No ternary compound is observed in all of the isotherms. Solid solubility of each phase is confirmed by chemical analysis by wavelength dispersive X-ray spectroscopy (WDS). The direction of the solubility lobe of L1 2-Ir3X with Al addition is explained in terms of the nearest neighbor interactions. Liquidus surfaces are also established by taking into account the microstructure of as-cast alloys, differential thermal analysis (DTA) data, and the Ir-Al and the Ir-X binary phase diagrams reported previously.
KW - High temperature alloys
KW - Intermetallics
KW - Scanning electron microscopy
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U2 - 10.1016/j.jallcom.2004.11.029
DO - 10.1016/j.jallcom.2004.11.029
M3 - Article
AN - SCOPUS:18244391707
VL - 395
SP - 263
EP - 271
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
SN - 0925-8388
IS - 1-2
ER -