Dynamic Compressive Properties of Zr-based Amorphous Matrix Composites Reinforced with Tungsten Continuous Fibers or Porous Foams

Abstract

In this study, amorphous matrix composites, whose matrix was a Zr-based amorphous alloy and reinforcements were tungsten continuous fibers or porous foams, were fabricated by the liquid pressing process, and their dynamic compressive properties were investigated. Approximately 65 to 69 vol pct of tungsten fibers or foams were distributed homogeneously in the amorphous matrix, whereas defects such as misinfiltration or pores were eliminated. According to the dynamic compressive test results of the tungsten-fiber-reinforced composite, tungsten fibers worked to withstand a considerable amount of applied loads, whereas the amorphous matrix sustains bent or bucked fibers, thereby leading to the maximum strength of 3328 MPa and the plastic strain of 2.6 pct. In the tungsten-foam-reinforced composite, the compressive stress continued to increase according to the work hardening after the yielding, thereby leading to the maximum strength of 3458 MPa and the plastic strain of 20.6 pct. This dramatic increase in maximum strength and plastic strain was attributed to the simultaneous and homogeneous deformation at tungsten foams and amorphous matrix because tungsten foams did not show anisotropy and tungsten/matrix interfaces were excellent. These findings suggested that tungsten-foam-reinforced composite could be applied to penetrators, in which the self-sharpening should be well promoted while keeping high specific gravity, sufficient strength, and plastic strain because cracks were formed at some heavily deformed tungsten foams by the shear fracture.