Uncertainty studies of topographical measurements on steel surface corrosion by 3D scanning electron microscopy

Abstract

Pitting corrosion is a damage mechanism quite serious and dangerous in both carbon steel boiler tubes for power plants which are vital to most industries and stainless steels for orthopedic human implants whose demand, due to the increase of life expectation and rate of traffic accidents, has sharply increased. Reliable methods to characterize this kind of damage are becoming increasingly necessary, when trying to evaluate the advance of damage and to establish the best procedures for component inspection in order to determine remaining lives and failure mitigation. A study about the uncertainties on the topographies of corrosion pits from 3D SEM images, obtained at low magnifications (where errors are greater) and different stage tilt angles were carried out using an in-house software previously developed. Additionally, measurements of pit depths on biomaterial surfaces, subjected to two different surface treatments on stainless steels, were carried out. The different depth distributions observed were in agreement with electrochemical measurements.

Correlative Fractography: Combining Scanning Electron Microscopy and Light Microscopes for Qualitative and Quantitative Analysis of Fracture Surfaces

“…The edges shadowing is less pronounced in this case, and both SE and BSE signals emerge from a thin surface region, but the contrast is reduced and the topographic aspect is not so pronounced as at high voltages (Joy & Joy, 1996). These distortions in surface contrast on SEM images cannot be avoided by other techniques, such as the stereo-pair reconstruction (Hein, 2001; Kang et al, 2012).…”

Three-dimensional surface reconstruction and in situ site-specific cutting of the teliospores of Puccinia miscanthi causing leaf rust of the biomass plant Miscanthus sinensis

“…The enhanced images not only assist the viewers in discriminating between projections and depressions but also elucidate spatial relationships, helping determine the distances between features (Bozzola and Russell, 1999). Such a stereoscopic technique has been used to improve topographic reliefs of the SEM micrographs of microscopic plankton (Andruleit et al, 2006) and mammalian erythrocytes (Hortolà, 2009), and thereby facilitating more comprehensive studies of their morphology (Kang et al, 2012).…”

Effect of alignment angle on the alignment accuracy of a miniature rotation robot for microscopy imaging

“…Rotating stages or cameras enables us to observe samples from multiple directions. 12,13 But the tilt angle of existing stages is usually below 90 , which renders some sample's surfaces still invisible. Also samples are likely to move out of microscope's field of view (FOV) during rotation.…”