Avaliação da resistência mecânica das juntas da gaiola de mini-baja soldadas pelo processo ER

Abstract

The objective of this work was to verify the quality and to evaluate the mechanical strength of welded joints by the shielded metal arc welding method in thin wall tubes (1.6 mm) and 25,4 mm of diameter used by Equipe Cerrado Baja SAE of the Federal University of Uberlândia. All welding procedures were performed with the intention of revealing the advantages and limitations for a future application by students of the mini-baja team. A comparison was made between rutile electrodes of types E6013 (carbon steel), E308 (stainless steel) and a basic coating electrode E7018 (structural steel), evaluating penetration, finishing, ease of welding and performing destructive tests for evaluation of mechanical resistance and process compliance. The tests demonstrate that all three electrodes provide satisfactory results as long as there are no weld bead defects, and a relatively short training time can enable a student to perform an acceptable weld quality using the 2.5 mm diameter E308 type rutile electrode by an inverter type power source which provides continuous current and promotes process stability. The results show that the quality of welding using stainless steel electrodes in this application is satisfactory, as well as the ease of extracting such quality from the process, showing itself the most economically viable and easy to handle process.