In this study, we use THz-based spectroscopy as a non-destructive diagnostic tool to characterize the corrosion by-products (rust) on aged iron structural components. Even though previous Mossbauer spectroscopic findings suggested the presence of an anti-farromagnetic resonance transition (AFR) in the spectral region for rust, the AFR transition has been found to be weak. On the other hand, a strong transition around 24 cm-1 (725 GHz) has been repeatedly measured in reflection mode. The origin of the spectral feature has been associated with the broad vibrational density of states in the low energy region, which is characteristic in disordered polycrystalline materials. From the initial study, the characteristic length scale of the inhomogeneous structure is estimated to be on the order of several to 10s of nm.
Proceedings Title: Symposium O: New Methods in Steel Design--Steel Ab Initio
Conference Dates: November 29-December 3, 2010
Conference Location: Boston, MA
Conference Title: Materials Research Society Fall Meeting
Pub Type: Conferences