ABSTRACT
The mass reduction of engineering structures is one of the basic trends nowadays, which can be attained by applying high strength steels. During the manufacturing of these structures, the main joining technology is the welding, and gas metal arc welding (GMAW) is the most frequently used fusion welding process. Furthermore, cyclic loads are the most dangerous loads, which occur in case of different engineering structures. Accordingly, the determination and application of different design or limit curves is a global trend for the innovative and economical design and operation of the structures. The purpose of the paper is to present the determination of high cycle fatigue and fatigue crack propagation design or limit curves for S690QL type high strength steels and their GMAW joints, under different matching conditions. The determined design limit curves can be applied for engineering critical assessment and structural integrity calculations of cracked, cyclic loaded structures or structural elements.
