Enhancing mechanical properties of Ti-64 alloy through ECAE: lubricant optimization, microstructural evolution and optimal process parameters

Abstract

This study explores the application of Equal Channel Angular Extrusion (ECAE) in enhancing the microstructural and mechanical properties of Ti-64 alloy. Finite Element (FE) analysis validates experimental outcomes, revealing a significant reduction in grain size, improved strength, and hardness. Microstructural analysis indicates dynamic recrystallization, transforming larger alpha (?) grains into smaller ones. Tensile testing demonstrates increased yield and ultimate strength in ECAE-treated specimens due to decreased grain size and heightened dislocation density. Lubricant optimization achieves low friction coefficients (0.02 and 0.04), reinforcing ECAE effectiveness. FE simulations and ANOVA analysis identify influential factors, leading to optimal parameter combinations. Isothermal ECAE successfully reduces grain size, resulting in substantial improvements in yield strength, ultimate strength, and hardness. These findings highlight ECAE's efficacy in enhancing the mechanical properties of Ti-64 alloy, with specific applications in biomaterials, particularly dental implants and bone support, as well as aerospace fasteners, where Ti-64 contributes to increased fuel efficiency, reduced emissions, and enhanced structural integrity. © The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature 2024.