01999nab a2200205 4500 20260520000854.0 260224s2010 xxu Corrosion behavior of Ti-6AI-4V with different thermomechanical treatments and microstructures jun. 2010 02/07/2010 ; 01/07/2010 9 p. ; 065004 Transcripción del resumen del autor: The corrosion behavior of four different microstructures of Ti-6Al-4V with varying volume fractions of primary a (0, 10%~20%, 40%~50%, and ~90%) was investigated in sodium chloride (NaCl) and hydrochloric acid (HCl) solutions. The microstructure constituent morphologies and distributions were characterized with optical and scanning electron microscopy (SEM) while constituent compositions were determined with energy-dispersive x-ray (EDX) analysis. All four microstructures exhibited spontaneous passivity in 0.9% NaCl at 37°C and active/passive transitions in 1.5 M HCl at 37°C. Very little difference in corrosion rate was observed using potentiodynamic polarization curves and weight-loss tests. However, SEM analysis of corroded surfaces indicated that the fully lamellar structure (0% primary a) exhibited the worst attack. Analysis of surfaces after 48 h immersion in 3.5 M HCl revealed that a/ß phase boundaries were preferential sites for corrosion attack. Also, ß phase in lamellar structures exhibited preferential dissolution in comparison to a phase. The corrosion results are discussed in terms of microstructure and constituent composition. In particular, the extent of partitioning of vanadium to the ß phase during heat treatment varies with the volume fractions of primary a and transform ß, which affects the corrosion performance in aggressive environments. 6 Corrosion 66 ARTICULO Atapour, M. 43345 Pilchak, A. 43346 Frankel, G.S. 27480 171638 171638 0 0 0 0 239457 BAAB BAAB 2026-03-05 200046503 0 200046503 2026-03-05 15:14:03 2026-03-05 ARTICULO