Quantifying the dependency of uniform corrosion of structural steel on grain size

The dependency of uniform corrosion of structural steel on the average grain size (D) should be quantified for design purposes. In the present work, a spectrum of grain sizes was obtained by simple heat treatment routes in st37 structural steel. It was revealed that the corrosion current density (icorr) increased by grain refinement, which was related to the increased density of grain boundaries. The data on the plots of hardness and icorr versus 1/√D were successfully fitted by a straight line and an exponential function, respectively. Therefore, the mechanical response was rationalized by a HallPetch type relationship with a slope of 237.8 MPa/µm0.5. Moreover, the obtained simple relationship between icorr and 1/√D can be used for prediction of the dependency of uniform corrosion on the average grain size.