DC Stray Current Corrosion Behavior of Pipeline Steel Based on Fractal Theory

The influence of DC stray current, soil conductivity and pH on the corrosion behaviors of Q235 pipeline steel was investigated based on the fractal theory of nonlinear science. The corrosion rate and fractal dimension of corrosion morphology were tested using corrosion coupon weight loss and box dimension methods, respectively. The focus is on the relationship between corrosion rate and fractal dimension. It is found that the DC stray current corrosion morphology of Q235 steel has fractal characteristics and the fractal dimension has exponential relation with corrosion rate. Stray current density has obvious effect on the corrosion behavior of Q235 pipeline steel. The fractal dimension shows exponential increase with the increase of stray current density, while it increases slightly with the increase of soil conductivity and the decrease of pH.