Possibility of replacing low-carbon construction steels with high strength steels for producing the welded structures in heavy machinery industry

Abstract

Modern trends of research and development of new products are focused on saving materials through mass reduction of various parts, so the high strength steels (HSS) are used more often than the conventional low-carbon structural steels. It is well known that the HSS’s high strength is providing the possibility for parts to be produced with smaller dimensions and cross-sections. This often results in the weight decrease of parts and whole structures. Here are presented results on an attempt to replace commonly used, low-carbon, structural steel S235JR, which has good weldability, with high strength steel, in industry of heavy machinery. The main objective is weight reduction, while keeping the adequate load carrying capacity and reliability of structures. The structural steel P460NL1 was analyzed, as well as advantages and disadvantages of HSS application, complexity of selecting the adequate welding method, filler materials and welding technology. After the trial welding on samples, experimental verifying of important mechanical and microstructural properties was conducted of the applied replacement steel.