Corrosion and mechanical behavior of a new Q450 weathering steel

Abstract

Weather-resistant steel represents a significant advancement in addressing corrosion challenges. Several types of steel with enhanced weather resistance have already been developed and manufactured. Weathering steel has shown excellent anti-corrosion ability over conventional structural steel. However, research on the corrosion and mechanical behavior of this type of steel after corrosion damage is still limited. Therefore, this paper conducts a detailed experimental investigation of the corrosion behavior and tensile strength of a new Q450 weathering steel after an accelerated corrosion test. Several scanning techniques were employed to examine the development of corrosion damage in the new Q450 weathering steels after being subjected to different corrosion times. Vickers hardness and velocity intensity of the corroded specimen were obtained to reveal the corrosion behavior of the Q450 steel. Based on the test data, predictive models were developed to predict the pit size and mechanical properties of Q450 steel after corrosion damage. The results suggest that, as the corrosion time increases, the types and amounts of corrosion products change significantly, which causes the passivation film to become much denser. Meanwhile, the mechanical properties are degraded by the increasing corrosion damage. Ultimately, the proposed predictive models are proven to be accurate and reliable.