Phase diagram of Au-Al-Pd at 500 °c

Abstract

The isothermal phase diagram of Au-Al-Pd at 500 °C was constructed using diffusion couples and equilibrated bulk alloys. Electron microprobe analyses were used to determine the phase compositions and phase relationships. Thirteen three-phase equilibria and two ternary phases (T1 and T2) were identified in this study. Phase T1 contained 37 at% Au, 26 at% Pd, and 37 at% Al. Phase T2 contained 44 at% Au, 24 at% Pd, and 32 at% Al. The Au solubility in the Al3Pd2, AlPd, and AlPd2 phases were 6, 15, and 34 at%, respectively. The Pd solubility in the AuAl2, Au2Al, Au8Al3, and Au4Al phases were 5, 10, 13, and 3 at%, respectively.