Research group

Solidification Processes and Complex Structures


Contact person

Dr. Daniel Şopu

Phone: +49 351 4659 878
Email:  d.sopu(at)ifw-dresden.de


Team

Projects

Publications

Devices and techniques

Composites with shape memory alloys


A straightforward strategy to produce bulk metallic glass heterostructures is to synthesize metallic glass composites. The improved ductility is generally ascribed to the increased amount of shear bands and their limited length given by the constraints of the crystalline phase. Moreover, those composites reinforced with crystallites which exhibit a martensitic transformation show pronounced ductility together with significant work-hardening. We provided a primary atomistic understanding of the deformation behavior and mechanisms of Cu64Zr36 composite structures reinforced with B2 CuZr nanowires by means of molecular dynamics simulations (see Figure). The phase transformation in the crystalline phase, which is normally driven by the elastic energy release, resulted in a decreased probability for the formation of mature shear bands and, consequently, an improved plasticity in the bulk metallic glass composite [1]. Further, we seek to understand the competing deformation mechanism in martensitic nanowires and glassy matrix, especially, the shear band nucleation induced by the martensitic transformation in crystalline precipitates and the intersection of a shear band with a shape memory inclusions.

[1] D. Sopu, M. Stoica, J. Eckert, Applied Physics Letters 106 (2015)211902/1-4 URL

Martensitic transformation in a BMG composite reiforced with CuZr B2 nanowires. Only those glassy atoms with an atomic strain higher than 30% are shown.