Deformation of Al₈₅Y₈Ni₅Co₂ Metallic Glasses under Cyclic Mechanical Load and Uniform Heating

Abstract

Modelling of the deformation process of Al85Y8Ni5Co2 amorphous alloys was carried out under simultaneous application of cyclic mechanical load (at 0.3 or 3 Hz frequencies) and continuously increasing temperature (heating rate 5 K/min). It is shown that deformation of the amorphous specimens occurs by the hyperbolic temporal dependence. It is analytically determined and experimentally proved that for non-isothermal cyclic deformation, the wave effects take place as a result of the superposition of thermal-activated and mechanical components. The behaviour of the material under thermo-mechanical action was described qualitatively within the framework of Spaepen’s model. The dependencies for the reaction force of the samples were obtained as two-parameter functions of the frequency and temperature. A reaction force surface of a specimen, as a function of the different forcing frequencies and time, has been plotted.

Keywords

• metallic glasses
• mechanical properties
• inorganic materials
• thermal expansion