Document Type
Paper
Keywords
Additive Manufacturing, Fatigue Life, Surface Integrity, Post-Processing
DOI
10.5703/1288284317938
Location
STEW 202
Start Date
25-9-2025 11:25 AM
Abstract
The qualification of electron beam powder bed fusion (PBF-EB) for safety-critical applications is hindered by variability in high cycle fatigue performance, largely due to surface roughness and internal defects. While Hot Isostatic Pressing (HIP) effectively reduces internal porosity, it does not address surface-initiated fatigue failures. This study investigated the combined effects of HIP and shot peening on enhancing the fatigue performance of PBF-EB Ti6Al4V. Over 50 specimens, including both vertical and horizontal build orientations, underwent high cycle fatigue testing per ASTM E466. X-Ray computed tomography confirmed decrease in defect distribution following HIP, while shot peening resulted in a more uniform surface. Combined HIP and shot peening led to a 100 MPa increase in fatigue compared to machined samples by introducing compressive residual stresses and delaying crack initiation. This study highlights the necessity of integrating combined post-processing strategies in extending the fatigue life of PBF-EB Ti6Al4V
Included in
Aerospace Engineering Commons, Materials Science and Engineering Commons, Mechanical Engineering Commons
Enhancing High Cycle Fatigue Perfomance Of Electron Beam Melted Ti6Al4V: A Study On Shot Peening And Hot Isostatic Pressing
STEW 202
The qualification of electron beam powder bed fusion (PBF-EB) for safety-critical applications is hindered by variability in high cycle fatigue performance, largely due to surface roughness and internal defects. While Hot Isostatic Pressing (HIP) effectively reduces internal porosity, it does not address surface-initiated fatigue failures. This study investigated the combined effects of HIP and shot peening on enhancing the fatigue performance of PBF-EB Ti6Al4V. Over 50 specimens, including both vertical and horizontal build orientations, underwent high cycle fatigue testing per ASTM E466. X-Ray computed tomography confirmed decrease in defect distribution following HIP, while shot peening resulted in a more uniform surface. Combined HIP and shot peening led to a 100 MPa increase in fatigue compared to machined samples by introducing compressive residual stresses and delaying crack initiation. This study highlights the necessity of integrating combined post-processing strategies in extending the fatigue life of PBF-EB Ti6Al4V