Scanning Kelvin Probe Force Microscopy as a means for comparative quantification of cold-rolling and visualizing the surface susceptibility to galvanic cells; compared to neutron diffraction and EBSD

High-Resolution Neutron Diffraction (HRND), Electron Back-Scatter Diffraction (EBSD) and Scanning Kelvin Probe Force Microscopy (SKPFM) techniques were used to comparatively characterize the surface electrical properties of Inconel 690 and stainless steel 316L alloys in cold-rolled and unrolled (annealed) conditions. Results indicated that a direct relation exists between the density of lattice defects (measured by HRND and EBSD) and heterogeneity of surface potential (measured by SKPFM). Mapping of the Volta potential and deconvolution of the corresponding histogram plots of the acquired data were utilized to visualize and comparatively quantify crystal lattice defects and estimate the surface susceptibility to the formation of micro/nano-galvanic cells. SKPFM was found as a reliable alternative to electron and neutron scattering techniques for comparative evaluation of energy states on alloys’ surfaces.