Authors: Erdinç KALUÇ, Alfred DHOOGE, Eddy DELEU
Abstract: In recent years, the use of high-strength low-alloyed steels in the automobile industry has increased considerably. For this reason, high-strength PROFILAR 400* (ZStE 380) steel sheets were welded using the MAG-welding and laser-welding processes using optimum parameters determined from previous investigations. In this study, overlap, butt and square- T joints were welded with semiautomatic and automatic (robotics) welding. Distortion measurements, metallographic examinations, hardness variations, bending, tensile and fatigue tests were carried out on the weldments. In order to examine the corrosion activity of the joints coated by phosphatation and cataforesis, they were subjected to a salt-spray test according to ASTM B-117 and also to a blister test. Mechanical tests showed that the MAG-welded joints responded better than those welded with laser, especially in overlap joints. The corrosion tests revealed that some slight corrosion occurred after 1000 hours.
Keywords: High-strength steel, MAG welding, Laser welding, Corrosion.