COMPUTER MODELS TO PREDICT CORROSION DEVELOPINGPROCESS BASED ON FRACTAL THEORY

摘要

Corrosion models of steels generally follow the power function W=T n, and they also fit with linearfunctions, W=K1×T and W=K2×T+C for the early and late corrosion stage. In this paper, the equationsbetween n in power function and K in linear function are obtained. For early stage, lgK1=a×(1-n), and forlate stage, lgK2=b×(n-1), (a and b are coefficients). Secondly, prediction corrosion models are simulatedbased on fractal theory and three probabilities are proposed to correspond to different surface conditions.The computer models are compared and validated by practical experiments. Finally, the relationshipbetween n in power functions and probabilities in models is also studied, the common expression islgn=a0–a1×lgp1+a2×lgp2–a3×lgp3(a0,a1,a2,a3 >0& a2=a1+a3).