Análisis de la resistencia a la tracción y evaluación metalográfica de juntas soldadas mediante proceso GTAW de aluminio grado estructural (ZICRAL)

Abstract

The objective of this project was to determine the tensile strength and metallographically evaluate structural grade aluminum welded joints using the GTAW process, whose selected aluminum was 7075 T6 for study. It began by carrying out both theoretical and experimental studies to identify the ideal parameters and the appropriate procedure for carrying out the welding; because the reaction that aluminum presents with oxygen (alumina) produces a great complexity to be welded. The varied parameters were current intensity and amount of protection gas flow, so that 9 cords were obtained. The visual inspection, metallographic preparation, hardness tests and tensile tests of these cords were carried out under standards. Using the scanning electron microscope (SEM, Scanning Electron Microscope) the chemical composition of the material was observed. The data obtained from all the tests were processed through graphs in Excel, it should be noted that the highest results were given for both hardness and traction in the welded joints that had an argon protection of 10 liters / min, however, it also has a great relation the amperage that was used. The microstructural evolution of the heat-affected zones and the fusion zones could be noted. In the same way, the influence that the composition has on the properties was analyzed. Finally, if a filler metal is used, it is recommended to look for one of the 5xxx series since it is still better for welding this aluminum alloy.