| This study examines the role of oxide composition on the general and localized corrosion of Fe(,32)Ni(,36)Cr(,14)P(,12)B(,6), Metglass 2826a, in acidic 0.1 M NaCl + 0.1 M Na(,2)SO(,4). 2826A and 304 stainless steel were assessed for: (i) general corrosion resistance by cyclic potentiodynamic anodic polarization, (ii) pitting corrosion resistance by potentiostatic anodic polarization and pit propagation rate testing and (iii) the degree of interfacial corrosion (crystallized 2826A) by electrochemical potentiokinetic reactivation testing.;Heat treatments consisting of two subcritical anneals (SC1, SC2), a high temperature crystallization anneal (MP), and a low temperature crystallization anneal (SS) were performed. SC1, SC2 and MP anneals decreased the general corrosion resistance relative to polished Metglass 2826A. However, the low temperature crystallization SS anneal produced the highest general corrosion resistance observed. Pitting current densities for nucleation and growth were lowered for all heat treatments compared to polished 2826A. Ranking of the corrosion resistance was correlated with the partitioning of elemental species by AES analysis and through the definition of interaction parameters. Important elemental interactions include Ni-P, Fe-Ni, Cr-B, Ni-B and P-B which varied with heat treatment, applied potential and the consideration of a 50 (ANGSTROM) wide interface between the oxide and the base glass.;Crystalline 304 stainless steel showed comparable general corrosion resistance to 2826A. A lower threshold for pit nucleation and higher pitting current densities were observed for 304 stainless steel compared to as-received or polished 2826A because of the structurally related pitting observed in 304 stainless steel. MP annealed 2826A displayed higher interfacial corrosion than sensitized 304 stainless steel because of the enhanced susceptibility of the Cr depleted MS-1 phase. SS annealing produced comparable interfacial attack to solution treated 304 stainless steel because of a refining of the distribution and type of phases present and the increased repassivation ability of the Cr enriched film formed on SS annealed 2826A.;The general corrosion resistance of 2826A was improved by mechanical polishing compared to the as-received ribbon. Polishing increased the threshold potential for pit nucleation but decreased the resistance to pit growth. AES analysis revealed polishing reduced the amount of S and increased the concentration of B in the passive film. |
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