Manufatura aditiva por soldagem a arco do aço AWS ER 308LSi: efeito da trajetória de deposição sobre a microestrutura e propriedades mecânicas

Abstract

Because of its capability to economically produce large-scale metal components with high production rates and low raw material waste, significant progress has been made in understanding of the Wire Arc Additive Manufacturing (WAAM) process. One of the factors attracted greater attention regarding the viability of its industrial employment is the determination of the employed deposition parameters effect on the manufactured components properties and performance. Therefore, the purpose of this work was to evaluate the effect of deposition path on the microstructure and mechanical properties of AWS ER 308LSi austenitic stainless steel components manufactured by WAAM. For this purpose, five distinct deposition path were evaluated and their influence was determined through the characterization of the shape (dimensional preform study, determination of surface ripple and deposition efficiency, determination of relative density), microstructure (identification of the phases present by optical microscopy and X-ray diffraction), and mechanical properties (characterization of tensile and impact strength, and microhardness measurements) of the deposits. The results show that the deposition path has an effect on the morphology and relative density of the deposited preforms. Likewise, it was found that, although the formed phases and the microstructure are independent of the deposition trajectory, the variation in the secondary dendritic arm spacing promotes differences in tensile and impact strength and hardness of the generated deposits. Based on the obtained results, it is concluded that there is a correlation between the deposition path and the formed deposits microstructural characteristics and, consequently, on its mechanical properties.