Abstract
The influence of structural changes such as structural relaxation and crystallization on the corrosion behavior of the [(Fe0.6Co0.4)0.75B0.2Si0.05]96Nb4 bulk glassy alloy has been investigated in aerated 0.1 and 0.5 kmol/m3 sulphuric acid solutions. All tests were carried out with the same materials in different states: as-cast and relaxed glassy and crystalline states. It was found that the multicomponent [(Fe0.6Co0.4)0.75B0.2Si0.05]96Nb4 glassy alloy had an ability to passivation in aerated sulphuric acid solutions irrespective of microstructure. The subsequent complete crystallization of the bulk glassy alloy leads to a significant decrease in corrosion resistance, while appropriate structural relaxation results in an increase in corrosion resistance. The corrosion results were discussed and correlated with the evolution of crystallization processes by means of XRD and DSC. The effect of temperature of the corrosive medium on the corrosion behavior of the as-cast [(Fe0.6Co0.4)0.75B0.2Si0.05]96Nb4 glassy alloy has also been analyzed.
