1. Effect of annealing and cobalt content on relaxation and crystallization behavior of zirconium based bulk metallic glasses
- Author
-
Rainer K. Wunderlich, Yue Dong, and Hans-Jörg Fecht
- Subjects
010302 applied physics ,Zirconium ,Amorphous metal ,Materials science ,Annealing (metallurgy) ,Physics ,QC1-999 ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Copper ,law.invention ,Amorphous solid ,Crystallography ,chemistry ,Chemical engineering ,law ,0103 physical sciences ,Endotherm ,Crystallization ,0210 nano-technology ,Cobalt - Abstract
The effects of annealing and cobalt content on relaxation and the crystallization process of Zr 64 Ni 10 Al 7 Cu 19 bulk metallic glasses were investigated. β-relaxation occurs during annealing, leading to increased endotherm before crystallization. α-relaxation during high temperature annealing (higher than Tg) affects the crystallization process. The introduction of cobalt leads to an inhomogeneous amorphous structure and two-step crystallization due to the positive mixing enthalpy between cobalt and copper. Non-affine thermal strain arising from low temperature annealing of heterogeneous structure leads to a reduced endotherm phenomenon during relaxation on the DSC curves and a reduction in hardness.
- Published
- 2017