Spatters during Laser Deep Penetration Welding with a Bifocal Optic

Abstract:

The energy efficient, high-speed laser deep penetration welding process is a technology which is increasingly used for industrial applications. In order to guarantee weld seams of high quality a stable process needs to be established. Especially when welding aluminium alloys the weld quality is reduced due to occurring spatters which entails a loss of material. Solidified spatters remain on the surface of the specimen after welding and need to be cleaned for further processing steps. One method to change the process behaviour is beam shaping. In this work, a bifocal optic is used to produce two foci along the beam axis in order to manipulate the energy input into the keyhole. Bead-on-plate welds are produced in aluminium alloy EN AW-6082 and mild steel S235. For comparison, welding is conducted using standard optics. The spatter occurrence is compared when using these different beam shapes. While a reduced number of spatters per time are observed the spatter size increases when using the bifocal optic in this study.

• Periodical: Advanced Materials Research (Volume 1140)
• Pages: 123-129
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1140.123
• Online since: August 2016
• Authors: Joerg Volpp*, Jennifer Srowig, Frank Vollertsen
• Keywords: In-Process Measurement, Laser Welding, Spatter Formation

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