Desenvolvimento de técnica de caracterização de inclusões não metálicas de aços com auxílio do software Imagej

Abstract

This work addresses the development of a methodology for the analysis of non-metallic inclusions to evaluate the cleanliness level of steels, more specifically that of Ultra Low Carbon steels, commonly used in automitive and household appliance industries. Steel samples supplied by a Brazilian steel mill were submitted to cleanliness characterization using the Yawata methodology, which has as its principle the classification of non-metallic inclusions by their general morphology, by means of optic microscopy, and, from that, rank them by their size and chemical composition. Furthermore, the freeware ImageJ was utilized to perform the measurements in photos taken by a camera attached to the optic microscope. The methodology was compared with the analysis results collected by an Automated Steel Cleanliness Analysis Tool, which is a special scanning electron microscope to analyze inclusions and classify them by their chemical composition using automatic punctual Energy Dispersive Spectroscopy. Therefore, it was verified that through Yawata’s methodology with the help of the software ImageJ and the images collected by an optic microscope’s camera, results in a low-cost methodology that is adequate to determine the cleanliness level of Ultra Low Carbon steels.