Analysis of Rain Erosion of Coated Materials

Abstract

The behavior of coat-substrate systems subjected to repeated impingements of liquid droplets was investigated. The systems studied consisted of a thick homogeneous substrate covered by a single layer of homogeneous coating of arbitrary thickness. Based on the uniaxial stress wave model, the variations of the stresses with time were determined both in the coating and in the substrate. Employing fatigue theorems, algebraic equations were derived which describe the incubation period and the mass loss of the coating past the incubation period, in terms of the properties of the droplet, the coating and the substrate. The results were compared to available experimental data and good agreement was found between the present analytical results and the data.