Effect Of Minor-addition Of MoSi₂on Microstructure And Properties Of Zr-Cu-Ni-Al Amorphou Alloys

Amorphous alloys are considered to be one of the most promising new structure materials due to their excellent mechanical properties. However, Amorphous alloys loaded under unconstrained conditions usually fail catastrophically with little global plasticity, which deformation behavior has limited the application of BMGs as engineering material so far. Therefore, preparation of amorphous alloys with strengthening and toughening properties have become one of the key problems of current research. A series of experimental studies were performed to explore the effect of minor-addition of MoSi2on the microstructure and mechanical properties of Zr-Al-Ni-Cu amorphous alloy in the present work. Some meanful results are achieved.A series of Add Zr-based metallic glass matrix composites with Zr2(Cu,Si,Al) crystal phase were successfully prepared by the minor-addition of MoSi2. Analysis performed on the composites indicates that the crystal phase has dendritic structure and is uniformly distributed closely combined with the substrate. The crystal size increased with minor-addition of MoSi2content increasing.Study on the compressive behaviors and fracture morphologies of the composites and Zr55Cu30Al10Ni5amorphous alloy reveals that the compression strength of the composite with the addition of3at.%MoSi2is approach to1650MPa, which is about10%higher than that of the Zr55Cu30Al10Ni5amorphous alloy. Observations on the surfaces of the composite demostrated that the crystalline phase prevent the propagation of shear band from a single direction and induced the interaction of shear bands. Thus the compressive strength of the composite is improved.The wear behaviors of composites with the addition of3at.%MoSi2is better than the Zr55Cu30Al10Ni5amorphous alloy. Zr55Cu30Al10Ni5amorphous alloy wear resistance of composite materials in join3at.%of MoSi2best, better than does not contain the MoSi2amorphous alloy. Analysis indicated that because the Zr2(Cu, Si, Al) the existence of the crystal phase, improve the hardness of the material, the wear mechanism is mainly abrasive wear and adhesive wear. With the increase of load, completely amorphous alloy wear mechanism mainly abrasive wear into the plastic flow is given priority to; Under certain stress, the second phase can have the effect of improving wear resistance, but when the normal load that beyond a certain range can lead to the second phase matrix wear resistance decrease instead.