The Chemical ecthing is defined as revealing the morphologic features of microstructure through the simultaneous process of reduction and oxidation, due to the electrolytic interaction with the surface of the samples, by defined absorption reduction and electrons (cathodic reduction) and through oxidation the emission electrons (anodic reaction), the microstructure heterogeneity result in areas of behavior and different characteristic in relation of the microstructure. The niobium is characterized by its excellent ductility, high corrosion resistance and reasonable resistance mechanical in high temperatures. It is applied in the superconductivity area by wire production of NbTi, Nb3Sn through cold forging rotative-swage. The aim of this work is to study the effect of chemical ecthing and features metallographic, according to the E 407-93 ASTM, the revealing microstructure, mechanical behavior of niobium deformed the cold forging rotative - swage and the evaluation of the analysis of behavior surface in Scanning Electronic Microscopic -SEM and as well as measurements microhardeness Vickers. It can be concluded that the ideal time chemical etching in the niobium was lesser for the greater reduction in area in the samples by necessary for features microstructure revealing and that longitudinal section showed lesser time in relation to transverse section.
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