多层金属膜厚度的无损测量研究

Research on Non-Damaging Measurement of Thickness Metal Plate with Multi-Layers

提出一种用电涡流传感器实现无损在线测量工件金属膜厚度的方法。给电涡流传感器同时施加３种不同频率的激励信号， 通过传感器与各层金属膜所感应的电涡流密度， 可以间接获得２ 层不同材料的金属膜厚度， 同时还可获得传感器与表层被测工件表面的距离。

This paper suggests a method for measuring the thickness of metal plate for working pieces on line using the eddy current sensors without any damage. The existing signals of three kinds with different frequencies are at the same time applied to the eddy current sensors. Measuring the sensors and eddy current density induced by metal plates in different layers may indirectly obtain the thickness of metal plates in different materials in working layers. And at the same time, the distance between the sensors and working pieces surface to be measured can be obtained.The theoretical analysis and experimental results indicate that this method is feasible.