A Valuable Method for on-line Wire Quality Control. Light Scattering from Cylindrical Rough Surfaces

摘要

In several applications, it is necessary to measure the surface characteristics of a wire so, it is important to do it during the manufacturing process. This work presentstwo main results: First, an analytical expression for the angular distribution of the mean scattered intensity from cylindrical rough surfaces as a function of the characteristic statistical parameters of the heights. This expression allows to measure the ratio T/σ between the correlation length and the roughness. Second, a quantitative relationship between the size and shape of the speckle grains in the Fraunhofer zone and the statistical properties of the cylindrical rough surface. In the first case, it is shown that the scanning process inherent to usual detection systems can be replaced by single step detection using a screen and a CCD camera. Therefore, this method can be applied to on line wire surface testing where conventional procedures are inadequate. In the second one, the experimental autocorrelation functions at different angles gives another method for masuring the parameter T/σ. Then, the study of the light scattered from cylindrical rough surfaces seem to be of great interest because of its potential application in NDT of manufacturing and finishing processes of components like pipes, junctions, wires and bearings.