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Abstract: Based on Miedema''s model, a Gibbs free energy diagram was first constructed for the Ag–Zr system and showed that the free energy of the Ag–Zr multilayered films could be higher than that of the corresponding supersaturated solid solutions and amorphous phase. Ion beam mixing with Ag90Zr10, Ag48Zr52 and Ag12Zr88 multilayered films was then conducted by 200keV xenon ions. It was found that an fcc supersaturated solid solution, a mixture of fcc and hcp metastable crystalline structures and an hcp supersaturated solid solution were formed and that amorphous phases were also observed to coexist with the metastable crystalline structures. The experimental observations concerning the non-equilibrium alloy formation matched well with the calculated Gibbs free energy diagram. [Copyright &y& Elsevier]

Abstract: The Cu12.6Zr40.5Al46.9 and Cu32.7Zr6.7Al60.6 amorphous alloys are synthesized in metallic multilayered films by ion beam mixing in the present study. Formation mechanism of amorphous phases is discussed in terms of the atomic collision theory. To further analyze the structure and composition of the obtained Cu–Zr–Al metallic glasses, structure factor S(q) is calculated based on the results of molecular dynamics simulations. It is found that the Cu12.6Zr40.5Al46.9 and Cu32.7Zr6.7Al60.6 metallic glasses are mainly consisted of Al–Zr and Al–Al, Cu–Cu amorphous phases, respectively. The calculated results turn out to match well with the experimental observation. [Copyright &y& Elsevier]

Abstract: Cu13Zr40Al47 amorphous phase was obtained in the CuZrAl metallic system by 200keV xenon ion beam mixing (IBM) in the irradiation range of 0.8∼4×1015 Xe+/cm2, clarifying that CuZAl metallic glasses with high concentration of Al could be experimentally obtained. We also found the mixtures of amorphous and crystalline phases newly formed in the Cu7Zr14Al79, Cu16Zr7Al77, Cu27Zr22Al51 and Cu84Zr9Al7 multilayered films. The possible formation mechanism of these resultant alloys is discussed in terms of the atomic collision theory. These experimental results also provide a substantial support to the results of molecular dynamics simulation, which presents a theoretical prediction of metallic glass favored region. [Copyright &y& Elsevier]

Abstract: A unique face-centered-cubic (fcc) Zr-based solid solution was obtained in the Cu10Zr76Ni14 multilayered films upon 200keV xenon ion beam mixing, accompanied by a novel phase transition sequence of Cu+Zr+Ni→dual-FCC→FCC→Amorphous while varying the irradiation dose. The energetic stability sequence, elastic stability and phonon behaviors derived from first-principle calculations jointly evidenced the metastability of fcc Zr from different perspectives. The experimental observations and theoretical calculations together justify the existence of an intermediate fcc Zr state under non-equilibrium conditions. Possible formation mechanisms for the metastable crystalline phase were also discussed in terms of the atomic collision theory. [Copyright &y& Elsevier]