a1 W.M. Keck Laboratory of Engineering Materials, California Institute of Technology, Pasadena, California 91125
To increase the toughness of a metallic glass with the nominal composition Zr57Nb5Al10Cu15.4Ni12.6, it was used as the matrix in particulate composites reinforced with W, WC, Ta, and SiC. The composites were tested in compression and tension experiments. Compressive strain to failure increased by more than 300% compared with the unreinforced Zr57Nb5Al10Cu15.4Ni12.6, and energy to break of the tensile samples increased by more than 50%. The increase in toughness came from the particles restricting shear band propagation, promoting the generation of multiple shear bands and additional fracture surface area. There was direct evidence of viscous flow of the metallic glass matrix within the confines of the shear bands.
(Received May 07 1998)
(Accepted May 03 1999)