Tensile behavior of Q890 and Q960 high-strength steel butt joints after corrosion

This paper delves into the tensile behavior of high-strength steel butt joints after exposure to corrosive environment. Single-V-groove butt joint specimens with the parent steel material of Q890 and Q960 high-strength steels and the feedstock wires of ER100S-G and ER120S-G were fabricated via robotic gas metal arc welding. A total of 39 corroded high-strength steel butt joint specimens were included with consideration of different plate thicknesses, parent steel-weld metal strength matching scenarios and corrosive environment exposure durations. The high-strength steel butt joint specimens were first exposed to neutral salt-spray accelerated corrosion environment. Non-contact 3D laser scanning and visual parametric analysis algorithm were employed to analyze the surface morphologies, and hence to determine the geometric features of corroded high-strength steel butt joint specimens. Degradation in tensile behavior of high-strength steel butt joints was further investigated via uniaxial tensile loading tests. The influence of mass loss due to corrosive environment exposure on the residual tensile loading capacities and mechanical properties of high-strength steel butt joint specimens is discussed. Twostage prediction models were proposed to accurately predict the residual tensile behavior of Q890 and Q960 high-strength steel butt joints after exposure to corrosive environment. The findings could guide the design and maintenance strategies for high-strength steel structures, ensuring their longevity and safety in marine applications.