Effect of sub-T_g annealing on the mechanical properties of a ZrAlNiCuNb bulk metallic glass

Abstract

The effects of isothermal annealing below the glass transition temperature (T _g) on the microstructures and mechanical properties of a Zr₅₆Al_10.9Ni_4.6Cu_27.8Nb_0.7 bulk metallic glass (BMG) have been investigated using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and compression and indentation testing methods. Sub-T _g annealing results in a reduction in the free volume and nucleation of nanocrystalline second-phase particles in the BMG. Complicated effects of the structural changes on the mechanical properties of the BMG were observed and these are discussed.

Keywords:

• mechanical properties
• metallic glass
• indentation
• electron microscopy
• nucleation

Acknowledgements

This study is supported by the Fundamental Research Funds for the Central Universities (2011JQ021), China–Australia Special Fund (51011120053), Australia–China Special Fund (CH090222), Hunan Provincial Natural Science Foundation of China (11JJ2024), the Program for New Century Excellent Talents in University (NCET-10-0842), and National Natural Science Foundation of China (50823006, 51021063).