Anisotropic Mechanical Properties of Tantalum-Continuous-Fiber-Reinforced Zr-based Amorphous Matrix Composites Fabricated by Liquid Pressing Process

摘要

Zr-based amorphous alloy matrix composites reinforced with tantalum continuous fibers were fabricated by the liquid pressing process, and their anisotropic mechanical properties were investigated by tensile and compressive tests of 0 deg (longitudinal)-, 45 deg-, and 90 deg (transverse)-orientation specimens. About 60 vol. percent of tantalum fibers were homogeneously distributed inside the amorphous matrix, which contained a small amount of polygonal crystalline particles. The ductility of the tantalum-continuous-fiber-reinforced composite under tensile or compressive loading was dramatically improved over that of the monolithic amorphous alloy, while maintaining high strength. When the fiber direction was not matched with the loading direction, the reduction of the strength and ductility was not serious because of excellent fiber/matrix interfacial strength. Observation of the anisotropic deformation and fracture behavior showed the formation of multiple shear bands, the obstruction of crack propagation by fibers, and the deformation of fibers themselves, thereby resulting in tensile elongation of 3 percent approx 4 percent and compressive elongation of 15 percent approx 30 percent. These results suggest that the liquid pressing process was useful for the development of amorphous matrix composites with excellent ductility and anisotropic mechanical properties.