Behavior of tungsten-particle-reinforced Zirconium-based bulk metallic glass composites when penetrating a semi-infinite target

This study investigates the penetration behavior of 50 % vol. W-reinforced Zr-based bulk metallic glass composites (W_p/Zr-BMGCs) with W particle sizes of 30, 75, and 250 μm using semi-infinite target penetration tests. The composites and craters were characterized via X-ray diffraction, optical microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The impact velocities during the tests were approximately 850 and 1250 m s⁻¹. The results show that the penetration depth of the W_p/Zr-BMGCs at high impact velocities is greater than that at low impact velocities. At similar impact velocities, the smaller the particle sizes constituting the reinforcing phase, the greater the penetration depth. Among the composites, W_p/Zr-BMGC with a W particle size of 30 μm achieves a maximum penetration depth of 10.62 mm at an impact velocity of 1283.8 m s⁻¹. During penetration, the Zr-based amorphous phase melts and W particles primarily undergo plastic deformation. Adiabatic shear bands generated during penetration promote the nucleation and propagation of voids and cracks, resulting in target-plate damage. High-speed penetration-induced unloading waves generate coronal cracks near the bottom of the crater, accelerating target-plate damage. The good penetration capability of the W_p/Zr-based amorphous composite with 30-μm W particles may be related to the beneficial effects of the small W particles on interfacial bonding.