Porosity in wire arc additive manufacturing of aluminium alloys

Hauser T, Reisch RT, Breese PP, Lutz B, Pantano M, Nalam Y, Bela K, Kamps T, Volpp J, Kaplan AF (2021)

Publication Type: Journal article

Publication year: 2021

Journal

Additive Manufacturing Elsevier

Book Volume: 41

Article Number: 101993

DOI: 10.1016/j.addma.2021.101993

Abstract

Wire Arc Additive Manufacturing is a near-net-shape processing technology which allows cost-effective manufacturing of large and customized metal parts. Processing of aluminium in Wire Arc Additive Manufacturing is quite challenging, especially in terms of porosity. In the present work, pore behaviour in Wire Arc Additive Manufacturing of AW4043/AlSi5(wt%) was investigated and a post-process monitoring approach was developed. It has been observed that as the shielding gas flow rate increases, the porosity in aluminium parts also increases due to the rapid solidification of the melt pool by forced convection. The higher convection rate seems to limit the escape of gas inclusions. Furthermore, gas inclusions escaping from the melt pool leave cavities on the surface of each deposited layer. Process camera imaging is used to monitor these cavities to acquire information about the porosity in the part. The observations were supported by Computational Fluid Dynamics simulations which show that the gas flow rate correlates with the porosity in aluminium parts manufactured by Wire Arc Additive Manufacturing. Since a lower gas flow rate leads to reduced convective cooling, the melt pool remains liquid for a longer period allowing pores to escape for a longer period and thus reducing porosity. Based on these investigations, a monitoring approach is presented.

Authors with CRIS profile

Benjamin Lutz

Involved external institutions

Luleå University of Technology SE Sweden (SE) Technische Universität Berlin DE Germany (DE) Technische Universität München (TUM) DE Germany (DE)

How to cite

APA:

Hauser, T., Reisch, R.T., Breese, P.P., Lutz, B., Pantano, M., Nalam, Y.,... Kaplan, A.F. (2021). Porosity in wire arc additive manufacturing of aluminium alloys. Additive Manufacturing, 41. https://dx.doi.org/10.1016/j.addma.2021.101993

MLA:

Hauser, Tobias, et al. "Porosity in wire arc additive manufacturing of aluminium alloys." Additive Manufacturing 41 (2021).

BibTeX: Download