Formation mechanisms of pores and spatters during laser deep penetration welding
Source abstract
Abstract
During laser deep penetration welding process, defects cannot be completely avoided yet. Due to the dynamic process, especially process pores and spatters occur. Keyhole dynamics are assumed to be responsible for the initiation of both pores and spatters. However, it is not completely clear yet how spatters and pores are formed. A semianalytical model of a keyhole is used to simulate dynamic keyhole properties of laser beam welding of aluminum. These are related to characteristics of spatters and pores occurring during laser deep penetration welding recorded using high-speed-imaging technique and x-ray analysis, respectively. Correlations of keyhole shapes and pore formation show that the volume underneath a keyhole collapse can be sufficient to capture the gas that is necessary for the formation of a pore and a keyhole expansion is not necessarily needed to produce the pores found in the weld seam. Calculated keyhole wall fluctuations are found to be not sufficient to detach spatters from the keyhole wall without additional forces from the melt pool.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Welding Techniques and Residual Stresses · Advanced Welding Techniques Analysis · Metal and Thin Film Mechanics
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Bremer Institut fuer angewandte Strahltechnik GmbH , Klagenfurter Straße 5, 28359 Bremen, Germany and , 971 87 Luleå, Sweden
Department of Engineering Sciences and Mathematics, Luleå University of Technology , Klagenfurter Straße 5, 28359 Bremen, Germany and , 971 87 Luleå, Sweden
Funding
Senatorin für Wissenschaft, Gesundheit und Verbraucherschutz of the country of Bremen
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Show source-provided references
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