CORRELATION OF MICROSTRUCTURE AND MECHANICAL PROPERTIES OF TANTALUM-CONTINUOUS-FIBER-REINFORCED AMORPHOUS MATRIX COMPOSITE PROCESSED BY LIQUID PRESSING

Abstract

A Zr-based amorphous alloy matrix composite reinforced with tantalum continuous fibers was processed without pores or misinfiltration by liquid pressing, and their microstructures and mechanical properties were investigated. About 60 vol pct of tantalum fibers were homogeneously distributed inside the amorphous matrix, which contained a few crystalline particles. The ductility of the composite under tensile or compressive loading was dramatically improved over that of the monolithic amorphous alloy, while maintaining high strength. The composite showed a high tensile elongation of 7.2 pct because of the formation of multiple shear bands, crack deflection in the matrix, multiple necking, and obstruction of crack propagation by ductile fibers. Under compressive loading, fibers prevented the shear fracture of the amorphous matrix and caused buckling of fibers, thereby leading to a high plastic strain of 45 pct or higher. This suggested that the liquid pressing process was useful for the development of continuous-fiber-reinforced amorphous matrix composites with improved ductility.