Open AccessMicrostructural Aspects of Twin-Spot Laser Welding of Dp-Hsla Steel Sheet Joints
Author(s) -
Sebastian Stano,
A. Grajcar,
Z. Wilk,
Maciej Różański,
Paul H. Matter,
Mateusz Morawiec
Publication year - 2016
Publication title -
archives of metallurgy and materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.258
H-Index - 29
eISSN - 2300-1909
pISSN - 1733-3490
DOI - 10.1515/amm-2016-0125
Subject(s) - materials science , welding , spot welding , laser beam welding , laser , composite material , laser beams , laser power scaling , joint (building) , metallurgy , optics , structural engineering , physics , engineering
The article presents the possibility of using twin-spot laser welding (i.e. laser welding with focusing a laser beam on two spots) for making overlap joints made of 0.8-1 mm thick HSLA and DP type high strength steel sheets. Joints were made using a Yb:YAG disc laser having a maximum power of 12 kW and a welding head by means of which it was possible to focus a laser beam on two spots, 0.6 mm and 1 mm away. The angle between focuses amounted to 0° or 90°, whereas the power distribution was 50%-50%. With settings as presented above it was possible to obtain high-quality overlap joints. The geometrical parameters of the joints were primarily affected by beams positions (in relation to each other) and, to a lesser degree, by the distance between the focuses. It was possible to obtain a 10% hardness reduction in the fusion zone of the DPHSLA steel joints if the angle between the beams amounted to 90°. The tests also involved microstructural examinations of individual zones of the joints