Characteristics of MAG Welded Joints Made in Fine-Grained High-Strength Steel S960QL

The paper presents the results of investigation performed in relation to butt welds made in steel S960QL using the MAG method. The research involved two types of welds, i.e. I (square butt weld preparation) and V-shaped. Metallographic tests enabled the determination of the HAZ area and helped identify structural changes in the heat affected zone. The neighbourhood of the fusion line revealed the presence of slight porosity. The analysis of the chemical composition of the HAZ and that of the weld indicated slight differences in their carbon equivalent values, indicating the proper selection of the filler metal. Microhardness tests indicated substantial differences of hardness between the fusion line and the weld. The weld characterised by square butt preparation revealed better characteristic.

doi: 10.17729/ebis.2018.6/5