Electrochemical corrosion response of a low carbon heat treated steel in a NaCl solution

✍ Scribed by W. R. Osório; L. C. Peixoto; L. R. Garcia; A. Garcia

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: German
• Weight: 969 KB
• Volume: 60
• Category: Article
• ISSN: 0947-5117
• DOI: 10.1002/maco.200805181

✦ Synopsis

Abstract

Dual‐phase (DP) steels are produced from a specific heat treatment procedure and have recently emerged as a potential class of engineering materials for a number of structural and automobile applications. Such steels have high strength‐to‐weight ratio and reasonable formability. The present study aims to investigate the effects of four different and conventional heat treatments (i.e., hot rolling, normalizing, annealing, and intercritical annealing) on the resulting microstructural patterns and on the electrochemical corrosion behavior. Electrochemical impedance spectroscopy (EIS) and Tafel plots were carried out on heat treated steel samples in a 0.5 M NaCl solution at 25 °C with neutral pH. An equivalent circuit analysis was also used to provide quantitative support for the discussions. The normalizing and the annealing heat treatments have provided the highest and the lowest corrosion resistances, respectively. The intercritical annealing and as‐received (hot rolled) low carbon steel samples have shown similar corrosion behavior. Although a deleterious effect on the corrosion resistance has been verified for DP steel due to the residual stress from the martensite formation, it combines good mechanical properties with intermediate electrochemical corrosion resistance.