Method for measuring resistivity of metallic iron under ultrahigh pressure

Abstract

The invention discloses a method for measuring resistivity of metallic iron under ultrahigh pressure. The method comprises the following steps that a high-purity iron sheet and a rhenium sheet are machined into a circular sample and a rectangular part by using a laser cutting machine respectively; the rhenium sheet is used as a heater, and the circular iron sheet, three tungsten wires and a tungsten-rhenium alloy wire are placed into an ultrahigh pressure testing device to be assembled; a test assembly block is placed in a cubic press, and is loaded to specified pressure and temperature, and the resistivity of the sample is measured and recorded by adopting a four-probe van der Pauw principle; after heating and data recording are completed, pressure is unloaded; and the circular iron sheetsample is taken out, fixed with epoxy resin, cut, ground and polished to obtain a longitudinal section of the circular iron sheet, the thickness is measured, and resistivity values of the metal ironsheet under different temperature and pressure conditions are calculated by using a van der Pauw measurement method formula. The problems that in the prior art, the temperature gradient is large, temperature measurement is inaccurate, measurement wires make contact with one another, resistivity calculation parameters are excessive, and errors are large are solved.

Description

technical field [0001] The invention belongs to the field of testing devices, in particular to a method for measuring the resistivity of metallic iron under ultra-high voltage. Background technique [0002] The resistivity of common metals, such as iron, nickel, copper, aluminum, etc. is very low, about ten to the negative eighth power and negative seven power ohms per meter. Accurately measuring the resistivity of these metals is particularly difficult. At atmospheric pressure, there are already many commercial metal resistivity measurement platforms and tools that are widely used in laboratories and industries. However, there is a lack of methods for measuring the resistivity of metals under ultra-high pressure and high temperature conditions. Because in the high-temperature and high-pressure generating device, the volume of the sample to be tested is limited, the arrangement of electrode wires is complicated, and it faces the risk of high failure rate under extreme temp...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is: to provide a method for measuring the resistivity of metallic iron under ultra-high pressure, so as to solve the problem that under ultra-high voltage conditions, the measurement results of resistivity of pure metal have large errors and large temperature gradients, making it impossible to test flakes. Samples and other technical issues

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