Method for measuring conductivity and thickness of metal material based on TMR sensor

Abstract

The invention discloses a method for measuring the conductivity and thickness of a metal material based on a TMR sensor. The method comprises the steps of establishing a probe assembly of the TMR-eddycurrent sensor; establishing an accurate conductivity-thickness factor two-dimensional grid model; and conducting reverse solving based on the accurate conductivity-thickness factor two-dimensional grid model. According to the method for measuring the conductivity and the thickness of the metal material based on the TMR sensor, the conductivity-thickness two-dimensional grid model is used as a physical model for actual thickness measurement; the precision of reverse solving is improved by increasing the density of the conductivity-thickness two-dimensional grid model, and reverse solving is performed by adopting the conductivity-thickness two-dimensional grid, so that the solving process can be simplified, and nondestructive detection of the conductivity and the thickness of the large-thickness metal material is realized.

Description

technical field [0001] The invention belongs to the technical field of non-destructive testing, in particular to a method for measuring the conductivity and thickness of metal materials based on a TMR sensor. Background technique [0002] During the service process of metal materials, there are often defects in the manufacturing process or use process (such as: manufacturing defects, corrosion, fatigue, impact damage, etc.), which will have a serious impact on the service of metal structures. If the damage in the structure cannot be found in time, it will often cause disastrous consequences. Therefore, it is urgent to use non-destructive testing technology for non-destructive testing of metal structures. The thickness of the metal material is often an important factor determining the strength of the metal structure. If the thickness of the metal becomes thinner due to the amplitude, the remaining strength of the structure will be insufficient and damage will occur. At the ...

AI Technical Summary

Problems solved by technology

The traditional eddy current sensor is composed of an excitation coil and an induction coil. In order to obtain a larger signal, the number of turns of the excitation coil and the induction coil is large, so the volume of the sensor is large, which is not conducive to the miniaturization of the sensor.

At the same time, due to the high excitation frequency of these eddy current sensors, the detection depth is limited due to the influence of the yield depth, which is not conducive to the detection of defects inside large-thickness metal structures and the measurement of the thickness of structural parts

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