Multi-Objective Optimization and Mechanism-Driven Microstructural Evolution of AA5083-H32 During Cold Rolling Using Hybrid Design of Experiments

Abstract

The mechanical and surface characteristics of cold-rolled AA5083-H32 aluminum alloy strips are examined in this study in relation to rolling speed, reduction percentage, and lubrication condition. Experiments were carried out at two speeds (44 rpm and 54 rpm), three reduction levels (40%, 45%, and 50%), and three lubrication states (SAE10, SAE20, and none) using an L18 orthogonal array design. In cold-rolled samples, mechanical characterization, such as tensile testing and Rockwell hardness measurement, showed increased tensile strength and hardness along with decreased elongation and yield strength, indicating a trade-off between strength and ductility. Surface roughness analysis showed the lubrication is the vital parameter for enhancing high surface quality and drastically reducing rolling power consumption.  SEM micro structural analysis revealed that surface deformation bands, second-phase particle alignment, and deformation-induced grain elongation and enrichment. Rolling speed was found to be the most important factor effecting surface hardness, surface quality structure and energy efficiency through statistical analyses such as ANOVA and Grey Relational Analysis by applying the optimisation technique. These results enable the optimization of cold rolling conditions to enhance the performance of AA5083-H32 alloy for domestic to industrial applications by offering a thorough understanding of the interaction between process parameters and material response methodology.