Microstructure and mechanical properties of Zr55Cu30Al10Ni5 amorphous alloy with high-energy states produced by strip casting

In this work, the twin-roll strip-casting technique was used to produce high-energy state Zr55Cu30Al10Ni5 (at%) amorphous alloy sheets. The effect of the temperatures of the alloy melt on their microstructure during production process was studied. The deformation mechanism of the fabricated pure amorphous alloy sheets, in addition to the effects of the formed crystalline particles in them, on their ductility and strength were investigated through mechanical property tests and in situ observations of their micro-deformation and microfracture processes. The results indicated that the formation and growth of crystalline particles in amorphous alloy sheets can be inhibited by increasing the melting and casting temperatures of the alloy melt. The fabricated high-energy amorphous alloy sheets exhibit significant plasticity in compression at room temperature, which was achieved through the sequential formation and cross growth of multiple shear bands. Moreover, the appropriate crystalline particles in the alloys could impede the linear propagation of the shear bands in the initial stage of compression deformation, which makes the alloys exhibit a certain level of work-hardening. However, with the increase in deformation, these crystalline particles became the source of the cracks in the alloys and accelerated their fracturing. Overall, this research provides an effective idea for regulating the microstructure and mechanical properties of amorphous alloys. In addition, it offers a significant guide for the industrial production of large amorphous alloy sheets. (C) 2020 Elsevier B.V. All rights reserved.