INVERSE ANALYSIS OF GALVANIC CORROSION - USING FUZZY A-PRIORI INFORMATION

A new method for estimating the galvanic corrosion rate is developed. In the case where the electrochemical polarization curves of metal in the electrolyte are available, the galvanic corrosion rate can be esti mated by solving the Laplace equation with boundary conditions based o n the polarization curves. The polarization curves, however, are not a lways available. In such a case, it is necessary to estimate the densi ty of the current across the metal surfaces from the potential values measured at points far away from the metal surfaces. Since this invers e problem is ill-conditioned, direct application of the conventional m ethod results in an oscillatory solution. To circumvent this problem, we formulate an inverse problem and employ the boundary element method to estimate the polarization curves. In addition, the estimation accu racy is improved by using a priori information which is expressed as f uzzy membership functions. Sample problems are also presented to demon strate the effectiveness of this new method.