EXPERIMENTAL TEACHING REFORM AND PRACTICE OF ELECTROMAGNETIC INDUCTION FOR ENGINEERING APPLICATIONS——TAKING THE DETECTION OF OIL LIQUID FERROMAGNETIC PARTICLES AS AN EXAMPLE

Detecting trace ferromagnetic wear particles in lubricating oil is important for assessing the degree and mode of wear in mechanical equipment. Based on Faraday's law of electromagnetic induction, this study presents an experimental apparatus for measuring ferromagnetic particle content using a self-developed sensor, an LM324 amplifier, a TLC549 A/D converter, an STC89C52 single-chip microcontroller, and a CH451 display driver chip. A non-intrusive measurement scheme for ferromagnetic particle detection is proposed. The quantitative relationship between variations in the detection signal and the amount of iron wear particles is established, enabling sensor signals to be converted into electrical outputs. Through static and dynamic experiments, the optimal operating parameters and detection accuracy of the system are determined. The results demonstrate that the apparatus can achieve non-contact quantitative detection of ferromagnetic particles. In addition to its engineering value, the device can also be used in college physics laboratory teaching as a verification experiment based on electromagnetic induction. Owing to its simple structure, it helps students develop hands-on skills and improve their ability to apply physical principles to practical problems.