基于电磁感应原理的球压试验压痕直径测试传感器研究

Research on Sensor for Measuring Indentation Diameter in Ball Pressure Test Based on Electromagnetic Induction Principle

球压试验中传统的压痕测量方法由于难以准确区分压痕的真实边界,很容易导致测量结果出现较大偏差。基于电磁感应原理的球压试验压痕直径测试传感器,应用了互感线圈轴向距离发生变化会引起互感电压变化的原理。在球压试验中,当球压试验装置在重力作用下向下发生位移时,互感线圈轴向距离变大,从而引起互感电压发生变化。通过试验对位移量与互感电压建立数学模型,可对球压试验装置的向下位移量进行定标。应用基于电磁感应原理的新型传感器,可较为准确地测量出施压装置向下的位移量并计算出压痕直径,为球压试验的结果判定提供较为准确的依据。在实际研究中,通过理论分析与大量的试验数据相关结合,验证了应用该传感器进行球压试验压痕直径测试的可行性。

The traditional method of ball-pressure test indentation size measurement is easily lead to larger deviation, because it is difficult to accurately distinguish the real boundary of indentation. The sensor for measuring indentation diameter in ball pressure test, which apply the principle that the change of axial distance of mutual inductance coil will cause the change of mutual inductance voltage. In the ball pressure test, when the ball pressure test device moved downward under the action of gravity, the axial distance of mutual inductance coil became larger, resulting in the change of mutual inductance voltage. The mathematical model of displacement and mutual inductance voltage can be established by experiment, and the downward displacement of the ball pressure test device can be calibrated. The new sensor based on electromagnetic induction principle, can accurately measure the downward displacement of the pressure device, and calculate the diameter of the indentation. It provides the basis for judging the results of ball pressure test. In practical research, through theoretical analysis and experimental data, the feasibility of using the sensor to measure the indentation diameter of ball pressure test is verified.