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| The Scanning Kelvin Probe (SKP) is a non-contact, non-destructive instrument designed to measure the surface work function difference between conducting, coated, or semi-conducting materials and a sample probe. The technique operates using a vibrating capacitance probe, and through a swept backing voltage, the work function difference is measured between the scanning probe reference tip and sample surface. The work function can be directly correlated to the sample surface condition. |
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| A unique aspect of the SKP is its ability to make measurements in a humid or gaseous environment. A topographical measurement of the sample surface is also possible which yields a relief map of the surface of the sample. Typical applications include coatings evaluations, corrosion measurements, weld analysis, semi-conductor circuit board analysis, and alloy heterogeneity analysis, to name a few. |
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The Scanning Vibrating Probe (SVP) operates with a non-intrusive scanning vibrating probe, measuring and mapping the microgalvanic electric field generated above the surface of an electrochemically active sample. A vibrating probe is used with a lock-in amplifier to eliminate noise occurring at any frequency other than the frequency of probe vibration.Probe vibration is controlled by a piezo-ceramic displacement device. Vibration amplitudes from 1 to 60 um in a direction perpendicular to the sample surface are possible.
Application areas for the SVP technique include, but are not limited to, pitting corrosion and pit development, evaluation of surface coatings and finishes, microstructure effects, stress corrosion and corrosion under flow. |
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| The Localized Electrochemical Impedance Spectroscopy system (LEIS) combines established principles of Electrochemical Impedance Spectroscopy (EIS) with proven scanning probe technology, providing enhanced capability to obtain spatially resolved impedance data rather than surface-averaged results from conventional EIS measurement techniques. The LEIS is designed to interface with EIS hardware, forming an integrated system composed of three major components: a high impedance input amplifier using a differential electrometer (LEIS); a lock-in amplifier (LIA) or frequency response analyzer (FRA); and a potentiostat. |
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The principles of LEIS are similar to those employed in traditional bulk EIS in that a small sinusoidal voltage perturbation is applied to a working electrode sample and the resulting current is measured to allow calculation of the impedance. However, rather than measure the bulk current, an electrochemical probe is scanned close to the surface, measuring the local current in the electrolyte. |
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