Statistical analysis of dislocation cells in uniaxially deformed copper single crystals

• Main Authors: Lipcsei, Sándor, Kalácska, Szilvia, Ispánovity, Péter Dusán, Lábár, János L, Dankházi, Zoltán, Groma, István
• Format: Journal Article
• Language: English
• Published: 21-07-2022
• Subjects: Physics - Materials Science
• DOI: 10.48550/arxiv.2207.10516

The dislocation microstructure developing during plastic deformation strongly
influences the stress-strain properties of crystalline materials. The novel
method of high resolution electron backscatter diffraction (HR-EBSD) offers a
new perspective to study dislocation patterning. In this work copper single
crystals deformed in uniaxial compression were investigated by HR-EBSD, X-ray
line profile analysis, and transmission electron microscopy (TEM). With these
methods the maps of the internal stress, the Nye tensor, and the geometrically
necessary dislocation (GND) density were determined at different load levels.
In agreement with the composite model long-range internal stress was directly
observed in the cell interiors. Moreover, it is found from the fractal analysis
of the GND maps that the fractal dimension of the cell structure is decreasing
with increasing average spatial dislocation density fluctuation. It is shown
that the evolution of different types of dislocations can be successfully
monitored with this scanning electron microscopy based technique.