Fatigue Failure from Inner Surfaces of Additive Manufactured Ti-6Al-4V Components

Autor: Joel de Jesus, José António Martins Ferreira, Luís Borrego, José D. Costa, Carlos Capela
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Materials, Vol 14, Iss 4, p 737 (2021)
Druh dokumentu: article
ISSN: 1996-1944
DOI: 10.3390/ma14040737
Popis: Selective laser melting (SLM) is an additive manufacturing process for producing metallic components with complex geometries. A drawback of this process is the process-inherent poor surface finish, which is highly detrimental in materials submitted to fatigue loading situations. The goal of this work is to analyze the fatigue behavior of Ti-6Al-4V specimens with internal axial channels under the following different conditions: hole drilled, hole as manufactured, and hole threaded M4 × 0.7. All the cases studied showed a lower fatigue performance as compared with solid samples due to the surface roughness and geometry effect that produced a surface stress concentration leading to a reduction in fatigue strength. The fractography revealed that crack initiation occurred from the internal surface in all specimens with internal channel mostly from defects as unfused particles and lack of fusion zones, while for the solid specimens crack initiation was observed from the external surface due to insufficient fusion defect. The application of the Smith-Watson-Topper energy-based parameter was revealed to be a good tool for fatigue life prediction of the different series studied.
Databáze: Directory of Open Access Journals
Nepřihlášeným uživatelům se plný text nezobrazuje