Uma nova abordagem para a medição da diluição de soldagem, baseada nos pontos de inflexão de um contorno ativo

Abstract

In several applications with dissimilar welding processes, the dilution can affect the mechanical properties of welded materials, because this method enables the occurrence of faults during normal service conditions. The dilution rate usually is calculated from the digital images analysis, aided by drawing programs that manually determine the areas of base metal melted and the weld metal region. However, this calculation process is characterized by being an exhaustive and error-prone due to operator fatigue. Thus, to reduce the analysis time and eliminate possible errors, this work proposes a new approach for the automatic determination of dilution rate. For this, the welded region is determined by the Balloon Active Contour Method. Then, the points that describe the separation line between the regions of base metal melted and filler metal added are determined automatically by calculating the inflection points of the Active Contour. Finally, the dilution rate is calculated considering the segmented areas properly highlighted by separation line. Tests are performed and compared to the results obtained by specialists using the traditional system, to evaluate the proposed approach. The results obtained were satisfactory for the application, as the proposed approach presented superior speed and precision than the methods found in the literature.