Microstructural Evolution and Mechanical Properties of Pure Aluminum upon Multi-Pass Caliber Rolling

Area of Science:

• Materials Science
• Mechanical Engineering
• Metallurgy

Background:

• Pure aluminum (Al) is a widely used material.
• Improving its mechanical properties is crucial for advanced applications.
• Room-temperature fabrication methods are desirable for energy efficiency.

Purpose of the Study:

• To investigate the effects of multi-pass caliber rolling on pure aluminum's microstructure and mechanical properties.
• To analyze the evolution of stress, strain, and temperature during the rolling process using finite element modeling (FEM).
• To correlate microstructural changes with enhanced mechanical performance.

Main Methods:

• Fabrication of pure aluminum using multi-pass caliber rolling at room temperature.
• Finite Element Modeling (FEM) simulations to analyze rolling forces, stress, strain, and temperature.
• Microstructural analysis including grain size measurement, dislocation density, and texture evolution.
• Mechanical testing to determine tensile yield strength (TYS), ultimate tensile strength (UTS), and elongation (El.).

Main Results:

• Increased rolling passes led to higher temperature, effective stress, and strain, while reducing maximum rolling force.
• Dynamic recrystallization (DRX) significantly reduced average grain size from 1 mm to 14 µm.
• Dislocation density increased, evolving into high-angle grain boundaries (HAGBs).
• Texture shifted from cubic to a mixture of Cube and Brass types.
• Optimal mechanical properties (TYS: 116 MPa, UTS: 135 MPa, El.: 17%) were achieved after 13 passes due to grain refinement.

Conclusions:

• Multi-pass caliber rolling is an effective method for refining the microstructure of pure aluminum at room temperature.
• The observed grain refinement and microstructural evolution directly correlate with significant improvements in mechanical properties.
• The study provides insights into optimizing caliber rolling parameters for enhanced aluminum performance.