Preparation, quasi-static, and dynamic compressive mechanical properties of BMG-W energetic structural materials

Abstract

In this paper, the Zr41.2Ti13.8Cu12.5Ni10Be22.5 amorphous alloy powder and the spherical W particles were used to prepare the BMG-xW (BMG=Bulk Metallic Glass, x = 10, 20, 30, 40, 50 vol%) energetic structural materials (ESMs) by spark plasma sintering. The research results on energy performance indicated that the Zr41.2Ti13.8Cu12.5Ni10Be22.5 alloy powder had excellent thermal reactivity, high combustion enthalpy and combustion integrity. The microstructure, quasi-static, and dynamic compressive mechanical properties of the BMG-xW ESMs were investigated. The quasi-static compression test showed that when the sintering temperature was 365 °C and above, the BMG-xW ESMs with the W content of 20 vol% to 50 vol% had similar fracture strengths and higher plastic deformation abilities than the BMG samples prepared under the same conditions. We have analyzed the plasticity enhancement mechanism of the BMG-xW ESMs. In addition, the failure modes of the BMG-xW ESMs were all shear fracture, which was conducive to exerting their shear self-sharpening. The Hopkinson compression bar test showed that the fracture strength and failure strain of the BMG-xW ESMs were greater than the Zr41.2Ti13.8Cu12.5Ni10Be22.5 BMG under dynamic compression at the same strain rate, and the higher the W content, the fracture strength and failure strain tended to increase. All samples showed obvious flame during dynamic compression. The larger the strain rate, the lower the W content, the shorter the ignition delay time, the faster the flame spreading speed and the longer the combustion time. The damage experiment confirmed that the BMG-xW ESMs had significantly superior damage performance than the Zr41.2Ti13.8Cu12.5Ni10Be22.5 BMG.