To solve the problem of pores in the weld bead of automotive axles, a study was made of the influence of various factors leading to the occurrence of porosity in steel joints welded by the robotic MIG/MAG process. Basically, the study focused on the influence the presence of a nitride-rich layer at the joint, the cleanliness of the surfaces to be welded, and the flow rate of the shielding gas. The results indicated that the presence of the nitride-rich layer generated by the plasma cutting process at the end of the tube corresponding to the base metal 1 significantly affected the resulting porosity in the weld bead. In addition to the experimental tests, practical tests were carried out on the shop floor in the axle production sector. Copyright © 2007 SAE International. (1991) Welding Handbook - Welding Processes, 2, pp. 109-154. , American Welding Society. 8th ed. MiamiMontgomery, D.C., Runger, G.C., (1996) Applied Statistics and Probability for Engineers, , New York, John Wiley e SonsMaia, I.G., (2005) Efeito da Camada de Nitretos Na Porosidade em Soldas de Eixos Automotivos, , 80 f. Dissertação (Dissertação de Mestrado) - Faculdade de Engenharia Mecânica, Universidade Estadual de Campinas, Campinas. BrazilTrevisan, R.E., Maia, I.G., Análise da Porosidade em Juntas Soldadas Pelo Processo MIG/MAG Robotizado, , 4° Congresso Brasileiro de Engenharia de Fabricação - COBEF, 15 a 18 de Abril de 2007 - Estância de São Pedro - SP - BrazilBarker, R.B., Pigma welding - A method for reducing weld porosity (1965) Welding Journal, pp. 1s-6s. , JanuaryVasil'Ev, K.V., Kokhlikyan, L.O., Weld porosity in welding on edges prepared by air-plasma cutting, and its prevention (1976) Welding Production, 23 (4), pp. 50-54Engblom, G., Formação de poros na soldagem de juntas cortadas com plasma de ar (1988) Encontro Nacional de Tecnologia da Soldagem, , 14, Gramado - BrazilSauders, H.L., (1997) Welding Aluminum: Theory and Practice, , 3th Ed. The Aluminum Association