Pressure and temperature effects on tensile strength and plasticity of metallic glasses

The effects of superimposed hydrostatic pressure and test temperature on the strength and plasticity of two different bulk metallic glasses have been determined. The effects of superimposed hydrostatic pressure on the global tensile strength and plasticity at test temperatures well below the Tg of the metallic glass are negligible, consistent with the minor effects of superimposed pressure on the elastic constants at these temperatures. However, increasing the test temperature produces tensile strength reductions and an increase in the global plasticity at 0.1 MPa. Superposition of hydrostatic pressure produces significant increases in strength and reduced ductility at temperatures approaching Tg for both a Zr-based and La-based bulk metallic glass. Potential source(s) of the pressure-induced changes in strength and global plasticity of the bulk metallic glasses are provided, and relate to pressure-induced increases in viscosity near Tg. (C) 2012 Elsevier Ltd. All rights reserved.