Vickers indentation-based assessment of dislocation density and substructure evolution in aluminum alloys
Jurij J. Sidor, János György Bátorfi
Abstract
The evolution of substructure and dislocation density in 1xxx and 5xxx aluminum alloys are analyzed in this contribution. The relationship between the deformed state and substructure evolution is done via indentation techniques and the implementation of numerical approaches. The indentation enabled to reveal the substructural aspects of microstructure development , while the numerical approximations successfully reproduced the experimentally observed evolution of dislocation density. A generic relationship for the assessment of cell size development in metals is presented and the proposed relation is in excellent agreement with the experimentally observed counterparts. Both model and material parameters, used for the assessment of dislocation density after various straining levels, are derived from the Vickers hardness profiles. The changes in the Tabor factor, Taylor factor , and geometric constant in the Taylor relation are analyzed by means of physically sound assumptions and well-established modeling approaches. The experimental findings and numerical analysis of substructure evolution allowed the determination of Stored Energy in examined Al alloys. It is shown that the driving force for recrystallization in metals can be determined from the indentation measurements under the condition that the material and process-dependent parameters are properly determined.