Stochastic modeling of pitting corrosion: A new model for initiation and growth of multiple corrosion pits A. Valor a , F. Caleyo b, * , L. Alfonso b , D. Rivas b , J.M. Hallen b a Facultad de Fı ´sica, Universidad de La Habana, San La ´ zaro y L, Vedado, 10400 La Habana, Cuba b Departamento de Ingenierı ´a, Metalu ´ rgica, IPN-ESIQIE, UPALM Edif. 7, Zacatenco, Me ´ xico DF 07738, Mexico Received 15 July 2005; accepted 30 May 2006 Available online 28 August 2006 Abstract In this work, a new stochastic model capable of simulating pitting corrosion is developed and val- idated. Pitting corrosion is modeled as the combination of two stochastic processes: pit initiation and pit growth. Pit generation is modeled as a nonhomogeneous Poisson process, in which induction time for pit initiation is simulated as the realization of a Weibull process. In this way, the exponential and Weibull distributions can be considered as the possible distributions for pit initiation time. Pit growth is simulated using a nonhomogeneous Markov process. Extreme value statistics is used to find the distribution of maximum pit depths resulting from the combination of the initiation and growth processes for multiple pits. The proposed model is validated using several published exper- iments on pitting corrosion. It is capable of reproducing the experimental observations with higher quality than the stochastic models available in the literature for pitting corrosion. Ó 2006 Elsevier Ltd. All rights reserved. Keywords: B. Modelling studies; C. Pitting corrosion 0010-938X/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.corsci.2006.05.049 * Corresponding author. Tel.: +52 55 5729 6000x54205; fax: +52 55 5729 6000x55270. E-mail address: fcaleyo@gmail.com (F. Caleyo). Corrosion Science 49 (2007) 559–579 www.elsevier.com/locate/corsci