The Mechanical Behavior and Microstructure of Additively Manufactured Ti6AI4V for Different Material States and Loading Conditions

Abstract

Selective laser melting (SLM) of Ti6Al4V is a very promising method to produce complex geometries for challenging impact applications. Hot isostatic pressing (HIP) is typically used to improve fatigue behavior, ductility and material reliability of parts produced by SLM. However, this treatment leads to an undesired deterioration of strength. The present study addresses that issue by investigating the effect of two different HIP conditions on the mechanical properties under compression and tensile loading for a strain rate range spanning up to 6 order of magnitudes and two different temperatures. We found a significant tensile-compression anisotropy in both flow stress and strain rate sensitivity depending on the HIP temperatures. These findings was correlated with microstructures and damage mechanisms.

Additively manufactured Ti‐6Al‐4V microstructure tailoring for improved fatigue life performance

“…The mechanical behavior observed should be interpreted to be representative of the loading orientation investigated for the microstructures shown in Figures 4-6. It is well established that other loading orientations, [27][28][29] microstructures, 25,[30][31][32] and chemistry [33][34][35][36] would exhibit different properties. The wrought material condition exhibited the greatest average yield stress of 1051 MPa, followed by the onestep annealing HT at 880 MPa (16.3% reduction from wrought yield stress).…”