3D characterization of defects in deep-powder-bed manufactured Ti-6Al-4V and their influence on tensile properties

Elambasseril, J, Lu, S, Ning, Y, Liu, N, Wang, J, Brandt, M, Tang, H and Ma, Q 2019, '3D characterization of defects in deep-powder-bed manufactured Ti-6Al-4V and their influence on tensile properties', Materials Science and Engineering A, vol. 761, pp. 1-10.


Document type: Journal Article
Collection: Journal Articles

Title 3D characterization of defects in deep-powder-bed manufactured Ti-6Al-4V and their influence on tensile properties
Author(s) Elambasseril, J
Lu, S
Ning, Y
Liu, N
Wang, J
Brandt, M
Tang, H
Ma, Q
Year 2019
Journal name Materials Science and Engineering A
Volume number 761
Start page 1
End page 10
Total pages 10
Publisher Elsevier B.V.
Abstract Deep-powder-bed additive manufacturing (AM) can lead to distinctive microstructural features. In this study, 300-mm long cylindrical rods (12-mm diameter) of Ti6Al4V were vertically built to the limit height of a commercial selective electron beam melting (SEBM) system for quantitative three-dimensional (3D) characterization of the defects by X-ray micro-computed tomography (μ-CT). Detailed μ-CT data from 18,337 consecutive slices revealed a strong dependence of defect characteristics on build height, including defect volume, population, sphericity, major axis length, depth and orientation angle. The first 100-mm build exhibited the worst presence of defects by each measurement, while the middle and last 100-mm builds contained much fewer defects, especially the last 100-mm build, which was free of lack-of-fusion defects (sphericity < 0.5). As a result, the first 100-mm build displayed 50% lower reduction of area and 20% lower strain-to-fracture than the last 100-mm build, while the tensile strengths varied within just ±3%. An outer 3-mm thick ring and a central 1.5-mm diameter region were found to contain substantially less defects along the 300-mm build height. The dependence of defect features on build height was attributed to the existence of an upward temperature gradient during SEBM. The 3D defect features revealed by μ-CT along the build height provide important implications for deep-powder-bed AM by SEBM.
Subject Metals and Alloy Materials
Keyword(s) Additive manufacturing
Defect
Lack of fusion
Porosity
SEBM
Ti-6Al-4V
DOI - identifier 10.1016/j.msea.2019.138031
Copyright notice © 2019 Elsevier B.V. All rights reserved.
ISSN 0921-5093
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 0 times in Thomson Reuters Web of Science Article
Scopus Citation Count Cited 0 times in Scopus Article
Altmetric details:
Access Statistics: 23 Abstract Views  -  Detailed Statistics
Created: Tue, 06 Aug 2019, 08:28:00 EST by Catalyst Administrator
© 2014 RMIT Research Repository • Powered by Fez SoftwareContact us