Thermodynamic approach of surface instability under irradiation Original Research Article

We analyze a model of deterioration of a solid material subjected to irradiation by energetic particles. In the frame of the thermodynamics of coherent phase transformations, the stability of the interface between the deteriorated layer and the undamaged substance has been investigated. Considering the linear regime of the roughness evolution, the growth rate of the surface fluctuations has been determined as a function of the relevant parameters of the problem: the shear modulus and Poissonʹs ratio of both phases; the thickness of the layer; and the initial stress. The wavelengths of the instabilities have been then calculated in the particular case of a metal/oxide interface of an irradiated zirconium alloy claddings used in nuclear power stations.