X-ray micro tomography study of internal defects of electron beam melted Ti6Al4V and their effect on fatigue behavior

November 12, 2020

Viktor Sandell (1), Thomas Hansson (2), Fredrik Forsberg (3), Henrik Lycksam (3), Pia Akerfeldt (1),Marta-Lena Antti (1)
MATEC Web of Conferences, 321, October 2020. DOI: 10.1051/matecconf/2020321030293


Abstract

In this work, the fatigue behaviour of Ti6Al4V manufactured using electron beam melting, its dependency on porosity, distance from the base plate and build layer height were investigated. XCT scans of the fatigue sample gauge lengths were correlated to SEM investigations of the fracture surfaces. A comparison between the top and bottom halves of the builds in terms of defect population and fatigue behaviour was also made. Larger pores were detected in samples with a larger build layer height and lower position in the build chamber. Results also indicate that part geometry and pore location, specifically closeness to the surface, are important factors regarding the initiation location of fatigue fractures at 1 % strain. Furthermore, a fatigue critical lack of fusion defect was undetectable in the XCT scan.


How Our Software Was Used

Dragonfly was used to analyze XCT data.


Author Affiliation

(1) Division of Material Science, Luleå University of Technology, 971 87 Luleå, Sweden.
(2) GKN Aerospace Sweden AB, 461 38 Trollhättan, Sweden.
(3) Division of Fluid and Experimental Mechanics, Luleå University of Technology.