Actually, one of the biggest challenge for the national electrical aluminum conductors industries has been the occurrence of non-metallic inclusions. These inclusions cause the rupture of the wires during the rolling, drawing and bunchering process. Then, the presence of non-metallic inclusions in these materials has significant impact in the capacity of small diameter wire's production, such as to reach rigorous requirements of strength's resistance and fatigue established for these materials. This study analyzes the aluminum wire's non-metallic inclusions that have caused those rupture during the drawing process, using conventional metallographic method with Scanning Electron Microscope (SEM) connect to an energy-dispersive spectrometry (EDS), in order to identify the inclusions' source. It was also developed a method of isolation of non-metallic inclusions by dissolving the aluminum matrix in a HCl solution. The analysis of isolated inclusions allowed a ampler investigation of the size, form and amount of the inclusions. The results showed that the inclusions responsible by wires' break are of the alumina type and their source is the aluminum oxide dragged of part of the layer that protects the liquid metal in the chutes covered with refractory material.
Non-metallic inclusions; Scanning Electron Microscope (SEM); Energy-Dispersive Spectrometry (EDS); electrical conductors
