Hot Isostatic Pressing Effects on Ductiles Fracture in Additive Manufactured Ti-6Al-4V Alloy: An Experimental and Numerical Approach

This study investigates the mechanical behavior of the Ti-6Al-4V alloy fabricated using electron beam melting through a hybrid experimental-numerical approach, focusing on ductile fracture under diverse loading conditions. A diverse specimen design is employed to evaluate fracture mechanisms in detail and to calibrate fracture models with high precision. The influence of porosity on mechanical behavior and fracture mechanisms is examined by comparing as-built specimens to those processed with hot isostatic pressing. Additionally, the effect of fabrication orientation relative to the build chamber on the mechanical properties of Ti-6Al-4V specimens is analyzed, offering insights into the behavior and optimization of additive manufacturing (AM) components. To predict fracture behavior, three numerical ductile fracture models-Johnson-Cook (JC), modified Mohr-Coulomb (MMC), and Hosford-Coulomb-are implemented using the VUMAT (User Material) subroutine. Based on these findings, a modified MMC model is proposed to address conditions involving both negative and positive triaxiality. The outcomes of this study provide a deeper understanding of the mechanical behavior of the Ti-6Al-4V alloy manufactured via AM, contributing to the improved design and optimization of AM components for industrial applications.