Investigation on Plastic Flow Behaviors of FCC Polycrystalline Aluminum under Pre-Cyclic Tension-Compression Loading:...

Area of Science:

• Materials Science
• Mechanical Engineering
• Solid Mechanics

Background:

• Understanding plastic flow behavior in metals is crucial for predicting material performance under cyclic loading.
• Pre-cyclic deformation can induce anisotropy, significantly affecting subsequent mechanical responses.
• Crystal plasticity models offer a powerful tool to investigate microstructural effects on macroscopic material behavior.

Purpose of the Study:

• To investigate the plastic flow behaviors of face-centered cubic (FCC) polycrystalline aluminum after pre-cyclic tension-compression deformation.
• To analyze the influence of pre-cyclic deformation on subsequent yield surfaces and plastic flow directions.
• To validate a physically based crystal plasticity model against experimental data.

Main Methods:

• Utilized a physically based crystal plasticity model incorporating back-stress.
• Employed a global finite element model (GFEM) of polycrystalline aluminum thin-walled tubes.
• Simulated tension-torsion stress space experiments, including yield surface measurements.

Main Results:

• Subsequent yield surface shape and plastic flow direction were dependent on offset strain levels and re-loading paths.
• Significant deviations in plastic flow direction were observed in the inverse pre-straining direction.
• The crystal plasticity model accurately reproduced experimental anisotropic evolution and plastic flow trends.

Conclusions:

• Pre-cyclic deformation profoundly impacts aluminum's plastic flow and yield surface evolution.
• The crystal plasticity model effectively captures anisotropic behavior induced by cyclic loading.
• The findings provide insights into predicting material response under complex loading histories.