title: Corrosion monitoring with speckle correlation.
abstract: The changes in the microtopography of a metal surface during a corrosion process are measured by decorrelation of the scattered speckle fields under coherent illumination. For that purpose a quantitative relation between the decorrelation of the scattered light fields and the rate of corrosion is established in a theoretical model, based on the statistics of phase and reflectivity changes of point scatterers at the surface. The speckle fields are recorded by a CCD camera and processed numerically in a computer, yielding the standard deviation of the topography changes with nanometer sensitivity. From the analysis of a series of images taken at equal time intervals during the corrosion process, the degree of interrelation among subsequent topography changes is calculated.
authors.affiliation: Department of Physics, Carl von Ossietzky University Oldenburg, D-26111 Oldenburg, Germany. frick@uwa.physik.uni-oldenburg.de
authors.forename: T
authors.initials: T
authors.lastname: Fricke-Begemann
authors.forename: G
authors.initials: G
authors.lastname: Gülker
authors.forename: K D
authors.initials: KD
authors.lastname: Hinsch
authors.forename: K
authors.initials: K
authors.lastname: Wolff