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Diffusion couples and equilibrated alloys were used to construct the isothermal phase diagram of Au-Al-Cu at 500°C. Electron microprobe analyses were performed to determine the phase compositions and phase relationships. Two ternary phases and 10 three-phase equilibriums were determined in this study. Four additional three-phase equilibriums were estimated to meet the criteria for phase relationships. The δ (Au 2 Al) phase exhibited a wide range of solubility, and the lattice parameters were examined by X-ray. The solubility ranges of the binary intermetallic phases were also determined.

This study describes the microstructure of a Zr-based alloy (Zr 63.36 Cu 17.22 Ni 11.47 Al 7.95 , at.%) under different cooling conditions. The Zr-based alloy can obtain completely amorphous structure, amorphous/nanocrystalline droplet and amorphous/crystalline composite structure by fast to slow cooling rate. It is interesting in the amorphous/nanocrystalline droplet composite that the average compositions of the droplet phase and amorphous matrix phase were same as the original alloy composition and the contrasts of BEI (back scatting image) were different. The droplet phase formed with (Al,Ni) 2 Zr 3 , and Zr 2 Ni(Al,Cu) nanocrystalline structures based on the analysis of XRD (X-ray diffractometry), EBSD (electron backscatter diffraction) and TEM (transmission electron microscopy). And Zr 2 Ni(Al,Cu) nanocrystalline phase transfers to the Zr 2 Cu(Al,Ni) phase after thermal treatment. The equilibrium phases of the alloy have been identified as Zr 2 Ni phase, Zr 2 Cu phase, Al 2 NiZr 6 phase and τ3 (Zr 51 Cu 28 Al 21 , at.%) phase which reach four phases equilibrium at 1,073 K for one week.

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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 (T 1 and T 2 ) were identified in this study. Phase T 1 contained 37 at% Au, 26 at% Pd, and 37 at% Al. Phase T 2 contained 44 at% Au, 24 at% Pd, and 32 at% Al. The Au solubility in the Al 3 Pd 2 , AlPd, and AlPd 2 phases were 6, 15, and 34 at%, respectively. The Pd solubility in the AuAl