On the Determination of Residual Stress in Coatings from Measured Longitudinal Deformation of a Substrate
MetadataNäita täielikku nimetuse kirjet
A method of measuring longitudinal deformation for determination of residual stresses in a long homogeneous cylinder by removal of thin cylindrical concentric layers was proposed by Heyn an Bauer . In [2-6] it is shown that computation of residual stresses is possible from the longitudinal deformation of a cylindrical substrate, measured during coating deposition. The present paper presents a generalized theory of the method of measuring the longitudinal deformation of a long cylindrical substrate for determination of initial residual stresses in coatings. Unlike in [2-6], the possibility of prestressing the substrate by an elastic element (spring) is taken into account . Special cases like (1) Poisson´s rations of the substrate and coating are equal, (2) Poisson´s ratios and the moduli of elasticity of the substrate and coating are equal, (3) a thin coating is applied on a rigid substrate, etc. are examined. A linear-fractional function is proposed for approximation of the dependence of initial stress on coating thickness.