Speakers - 2027

Title: Tensile behavior of Cu-coated Pd40Cu30Ni10P20 metallic glassy wire

Abstract

Catastrophic brittle fracture of monolithic metallic glass (MG) hinders the engineering application of MGs. Although many techniques have been tried to enhance the tensile ductility of metallic glasses, the improvement remains quite limited. Here, we show the effect of electrodeposited Cu coating on tensile plasticity enhancement of Pd40Cu30Ni10P20 MG wires, with different volume fractions of copper coatings (R), from 0% to 97%. With increasing R, tensile elongation is enhanced to 7.1%.

The plasticity enhancement is due to the confinement of the Cu coatings, which leads to multiple and secondary shear bands, according to SEM investigations. In addition, SEM images show that the patterns on the fracture surface of Cu-coated MG wires vary with the volume fraction of Cu coatings. The size of shear offsets decreases with increasing R. The viscous fingerings on the fracture surface of monolithic MG wire change into dimples on the fracture surfaces of Cu-coated MG wires with R values of 90% and 97%. The electrodeposition technique used in this work provides a useful way to enhance the plasticity of monolithic MGs under tensile loading at room temperature.

Key words: Tensile Plasticity, MG Wires, % Elongation, Bilayer Coating