M-h Curve Tester Of Labview-based Soft Magnetic Thin Films

Soft magnetic thin films are promising materials for modern magnetic devices. The magnetic hysteresis loop of the magnetic thin film is very important, because a lot of useful parameters can be extracted from it, for example, coercive force HC, saturation magnetization MS, remanent magnetization Mr and magnetic energy product. These parameters are helpful for the research and application of the soft magnetic materials. So when we test the magnetic characteristic of the soft magnet thin film, the magnetic hysteresis loop should be tested at first. It is of great practical significance for the scientific research and design to develop low cost, high precision, specialized instrument which can test the magnetic hysteresis loop of the soft magnetic thin film.In this paper, by using LabVIEW software platform of NI Corporation, microcontroller ADuC842 of ADI Inc, system error self-calibration and numerical integration, a measurement system special for the magnetic hysteresis loop testing of soft magnetic thin film were designed.The main works of the paper are as the following: The principle of testing the magnetic hysteresis loop of thin film which based on the law of electromagnetic induction was introduced at first; Then the whole scheme of the measurement system was designed based on the principle; At last, the hardware and the software of the measurement system, verified the performance of the system were developed and implemented.The main parameters of the instrument are as follow: Magnetic field: 50Hz, maximum 400 Oe, resolution 0.0131~0.1048 Oe. Measured Magnetization range: 0.006emu~ 0.1emu. Testing curve: M-H loop. Testing parameters: HC, MS, Mr .Additional performance: test data can be saved as Excel file, print the test report, failure self-diagnosis.It can be characterized by low cost, small size, simple operation and fast testing.