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Abstract: Micromechanical behaviors of Zr-based metallic glass/porous tungsten composite under quasi-static uniaxial compression at room temperature were investigated by in-situ high-energy X-ray diffraction (HEXRD) technique based on the synchrotron source and finite element modeling (FEM). During the process of compression, the main load phase was tungsten phase until it yielded at an applied stress of 1175MPa. Subsequently, metallic glass phase became the main load phase. The plastic misfit strain of the two phases resulted in stress concentration near interfaces between them, which accelerated the process of stress transfer from the tungsten phase to the metallic glass phase. The metallic glass phase started to yield at 1500MPa; at that time defects weakened the mutual restriction between the metallic glass phase and the tungsten phase, leading the tungsten phase to fail or the interfaces between two phases to separate by the increasing load. [Copyright &y& Elsevier]

The effect of temperature on the micro-deformation behavior of the porous tungsten/Zr-based metallic glass composite was investigated during cyclic compression by synchrotron based in-situ high-energy X-ray diffraction (HEXRD) and finite element modeling (FEM). Both the metallic glass phase and the tungsten phase remained elastic in the first loading at different temperatures. The metallic glass phase also exhibits “work hardening” behavior, which is attributed to the crystallization of the metallic glass phase during deformation at high temperature. The yield strength of the tungsten phase during the second loading decreased with the increase of temperature while remained almost equal in the third loading. Both the temperature and the pre-deformation from the cyclic loading have great influence on the work hardening behavior of the tungsten phase. The influence of the pre-deformation after the second cyclic loading is greater than the influence of the temperature during the third loading. [ABSTRACT FROM AUTHOR]

The micro-mechanical behavior of porous tungsten/Zr-based metallic glass composites with different tungsten volume fraction was investigated under cyclic compression by synchrotron-based in - situ high-energy X-ray diffraction (HEXRD) and finite element modeling (FEM). During cyclic compression, the dislocation in the tungsten phase tangled near the interfaces, indicating that the elastic metallic glass phase restricted dislocation motion and obstructed the deformation of the tungsten phase because of the heterogeneity in stress. After the metallic glass phase yielded, the dislocation tended to propagate away from the interfaces, showing the decrease of the interphase stress affected the direction of motion in the dislocations. The tungsten phase exhibited increased yield strength with the increase of cyclic loading number. Yield stress of the tungsten phase decreased with increasing the tungsten volume fraction during cyclic compression, which was influenced by the elastic strain mismatch between the two phases. The stress heterogeneity and the stress distribution difference between the two phases resulted in that the yield strength of the metallic glass phase decreased with the increase of tungsten volume fraction, and accelerated the formation of shear bands in the metallic glass phase as well as cracks in the tungsten phase. The heterogeneity in stress also excessed the interface bonding strength, inducing interface fracture near interfaces. [ABSTRACT FROM AUTHOR]