Fabrication of ZrAlNiCu bulk metallic glass composites containing pure copper particles by high-pressure torsion

Abstract

Several pairs of Zr55Cu30Ni5Al10 bulk metallic glass (BMG) plates and pure copper plates with volume ratio of 1:1 were put together and subjected to high-pressure torsion process with 10, 20 and 50 rotations separately to prepare BMG/Cu composites. For the samples processed with 10 and 20 rotations, the microstructures were not very homogeneous and some metallic glass blocks can still be observed near the center of the samples. While after 50 rotations, the microstructure becomes rather homogenous throughout the samples. Both glass phase and copper phase were transformed into small pieces and mixed uniformly with each other. No intermetallic compounds either from chemical reaction or crystallization from the glass phase could be detected for all the samples regardless of the rotation numbers. This study indicates that high-pressure torsion technique can be used as a new approach to fabricate bulk metallic glass matrix composites.