Potential correction device for Kelvin probe and use method

Abstract

The invention relates to a potential correction device for a Kelvin probe and a use method thereof. The device comprises a copper pipe, a copper partition at the middle part of the copper pipe, an injector and a saturated copper sulfate solution; the copper pipe is made of pure copper and has a diameter ranging between 2 mm and 5 mm; the copper partition is made of pure copper and has a thicknessranging between 0.5 mm and 3 mm; a small hole is formed in an intersection of the partition and the pipe wall of the copper pipe; the solutions above and below the partition are communicated through the small hole; the small hole has a diameter ranging between 0.3 mm and 0.6 mm; the saturated copper sulfate solution is a clarified solution; after the copper pipe is connected with the injector, thesaturated copper sulfate solution is injected, and a spherical liquid surface is formed at the lower port of the copper pipe; and in an environment that the relative humidity is more than 90 percent,the Kelvin probe with an upward pin is used to test a potential at the moment, and the potential is corrected to be 0.32 V. The potential detection device can correct the potential of the Kelvin probe with the upward pin, has the advantages of convenience in operation, accurate potential, high correction speed and the like, and is suitable for being popularized and applied in corrosion detectionand corrosion monitoring.

Description

technical field [0001] The invention relates to the field of surface engineering, in particular to a Kelvin probe potential correction device and a use method. Background technique [0002] The Kelvin probe (Kelvin probe) can be used to measure the potential of the metal surface. It is a fast and sensitive non-destructive monitoring technology, and has been widely used in corrosion detection and corrosion monitoring. Commonly used Kelvin probes can be divided into two types, ie, probe-down Kelvin probes and probe-up Kelvin probes. Calibrating the potential is a necessary step before using the Kelvin probe, and it is also the basic premise to ensure the accuracy of the measurement data. At present, the calibration of the probe-down Kelvin probe usually adopts the copper / copper sulfate electrode method. Add saturated copper sulfate solution to make the liquid surface spherical; (2) Make the probe close to the spherical liquid surface, measure the potential at this time accor...

AI Technical Summary

Problems solved by technology

However, the disadvantage of this method is obvious: the potential of the solid silver / silver chloride electrode may be changed by humidity, temperature, and pollutants such as carbon dioxide in the environment, resulting in inaccurate potentials and even serious errors.

In addition, the preparation of solid silver / silver chloride electrodes is very time-consuming, and its preparation process is complicated

These disadvantages severely limit the wide application of probe-up Kelvin probes

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