Welding method as influential factor of mechanical properties at high-strength low-alloyed steels

Abstract

In this paper the analysis of welding technology to mechanical properties of welded joints at high strength low alloyed steel S690QL is presented. Experimental testing was done at models with V-groove butt joints that are done by MMA or MIG for root pass and MAG for other passes of multipass welded joints with related parameters and consumables. Yield and tensile strength, so as answer to load of models are determined experimentally in order to analyses the effect of welding technology to resulted mechanical properties. On the basis of the obtained results it can be concluded that welding parameters have significant influence to mechanical properties of welded joints at high-strength low-alloyed steel. Furthermore, it can be concluded that welded joints with root pass done by MIG and other passes by MAG provide better mechanical properties. Presented research point out that welding parameters at high strength low alloyed steels must be selected and controlled precisely to obtain welding joints with adequate mechanical properties. Welding, as dominant method of joining, is primary factor that provide beneficial application of high-strength low-alloyed steels. The paper highlight the influence of material degradation due to welding. This paper point out the importance of analysing the welded joints at different levels of dimensions, while further, more detailed, research can be continued through development of a numerical model of the welded joints which will complete the experimentally obtained results. As experimentally obtained results correlate to material degradation due to welding it is implicated that future development of high-strength low-alloyed steels must be followed with development and modification of welding processes.