Resistencia al picado de Aleaciones Nanocristalinas de Al90Fe7Nb3 y Al90 Fe7Zr3obtenidas por Solidificación Rápida y Extrusión Caliente

Amorphous and/or nanocrystalline Al-based alloys have better mechanical properties when compared with crystalline conventional Al-alloys. Different techniques can be used to obtain amorphous Al-based alloys, usually in a ribbon form (from melt-spinning processing) or powders (from gas atomization or ball milling processing). To obtain bulk samples, that is, samples with dimensions typically much larger (mm scales) than the ones obtained from the above mentioned techniques (<40 μm), the ribbons or powders must be hot-consolidated. One of the most important challenges in the development of such alloys is to keep a refined microstructure after the necessary heating. The present work focuses the pitting resistance by electrochemical corrosion resistance test in solution 0.9 % NaCl and pH 7.0, for Al 90 Fe 7Nb 3 and Al 90 Fe 7Zr 3 nanocrystalline alloys, which were obtained by hotextrusion of mechanically alloyed powders, and melt-spinning process. The results of the polarization curves indicated that the Al 90 Fe 7Nb 3 and Al 90 Fe 7Zr 3 ribbons present better corrosion properties than the extruded alloys.