Abstract
Strong surface relaxation effects are found in the transmission conduction electron spin resonance (TESR) at aluminium foils coated by a thin zinc layer. The increase of relaxation rate varies linearly with the inverse of thickness of the aluminium foils and is independent of the direction of the propagation of the radiofrequency field through the sample. Using a phenomenological model due to Dyson (1955), the TESR lineshape is calculated and, in general, good agreement is found between experiment and theory.