Footprints of plastic deformation along strain gradients in twisted Au microwires

This proposal involves 3D Laue microdiffraction experiments within single crystalline cross-sections of twisted Au micro wires with a bamboo microstructure using the DAXM setup at BM32. The DAXM measurements can be used to determine both, the global and local deformation (strain and misorientation fields) in 3D as well as the corresponding density of GNDs as function of the radial position within the single crystalline cross-section of the wire. By comparing wires with different diameters for different degrees of deformation (shear strain at the surface is equal for every wire diameter), it will be possible to quantify the evolution of plastic deformation from the center to the surface in dependence of the wire diameter, and accordingly to quantify the impact of pure strain gradients on the observed size effects for strength and hardening behaviour for the first time.