%0 Journal Article
%A Chung, Woo-Sik
%A Hummel, M.
%A Spurk, C.
%A Häusler, A.
%A Olowinsky, A.
%A Häfner, C.
%A Beckmann, Felix
%A Moosmann, Julian
%T In situ X-ray phase contrast imaging of the melt and vapor capillary behavior during the welding regime transition on aluminum with limited material thickness
%J Welding in the world
%V 68
%N 1
%@ 0043-2288
%C Heidelberg
%I Springer
%M PUBDB-2024-00217
%P 43-50
%D 2023
%X The X-ray phase contrast imaging is a powerful method to understand the fundamental behavior of the melt and keyhole during the laser beam welding process. In this paper, the keyhole-induced vapor capillary formation in the melt pool is investigated by using an adjustable laser beam source. For this purpose, the aluminum A1050 specimen with a thickness of 0.5 mm is molten only with the heat conduction welding regime by using the ring-mode laser beam. Once the specimen is molten through, the core multi-mode laser beam is then applied to vaporize the melt and a transition to keyhole welding regime occurs. Therefore, the core multi-mode laser beam with an intensity value of 33.3 MW/cm2 is investigated. The correlation between the keyhole-induced vapor capillary and the melt behavior is further investigated in this paper which was recorded with a high sampling rate of 19 kHz. In addition, a theoretical calculation about the keyhole depth is discussed in this paper. 
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:001096596700001
%R 10.1007/s40194-023-01616-1
%U https://bib-pubdb1.desy.de/record/601487