Per: GABRIELA PAULA DE SOUZA (UENF), Bárbara Ferreira de Oliveira (UENF), Sérgio souto maior tavares (uff), Laryssa dos Santos Almeida (UFRJ), Sérgio Neves monteiro (IME), Lioudmila aleksandrovna matlakhova (uenf)
Abstract:
The present work presents an influence of two welding conditions on the microstructure of Inconel 625 deposited on AISI 4130 steel by PTA-P welding: condition 1 (current: 105 A, plasma gas: 1.7 L / min, rotation: 0, 29 rpm) and condition 2 (current: 130 A, plasma gas: 1.5 L / min, rotation: 0.26 rpm), in order to check the possibility of making coatings in a single layer, with a minimum Fe dilution. Microstructural characterization was carried out using confocal optical microscopy (MO), scanning electron microscopy (SEM), dispersive energy spectroscopy (EDS) of the base metal, interface and coating and X-ray diffraction (XRD) only in the coating. Hardness measurements were made along the cross-section of samples. The results showed that the metal base present a thermally affected zone of coarse grains. No martensite was observed at the base metal / coating interface, despite the condition 1 sample showing microcracks in this region. The coatings had a dendritic austenitic microstructure with dispersion of NbC carbides in the interdendritic region. In condition 2, there was an increase in the dilution of Fe, affecting the formation of NbC carbides and, consequently, the hardness of the coating. Thus, it is necessary to deposit two layers of Inconel on AISI 4130 steel