Desenvolvimento de programa computacional para medição semi-automática de altura, largura e profundidade do cordão de solda, e taxa de diluição

Abstract

The dilution of the weld is a process that causes the change of the compositional elements of the filler metal that, due to the fusion occurring in fractions of metal, is the emergence of a new compound to the fusion zone. One can measure the dilution rate by the percentage of the base metal found in the weld bead. There are some factors that influence this rate, among which the type of joint to be soldered, the temperature of preheating, consumables and welding parameters. In many applications, the dilution is a deterministic factor in the performance of the welded material. When soldering hard coatings low dilution is desirable that the chemical composition and properties of the weld deposit are minimally influenced by the properties of the base metal, usually much lower than the requirement to wear resistance. The measures of dilution, are usually performed manually with the aid of drawing programs by determining the area of the base metal melted and the total area of the weld metal. In this sense, this paper aims to present a computational system that performs semi-automatic measurement of the rate of dilution. This system uses techniques of Digital Image Processing, such as Active Contour Method, the technique of Growth Regions and filters for noise elimination. The results are consistent and show similar rates to the conventional method. Using this application become the measurement of dilution rate more efficient and less subjective.