History of VSM shaker is not so long as you imagined. Compares to the traditional closed-circuit hysteresis loop instrument, applied magnetic field relatives to the time of continuous change has more advantageous to obtain the corresponding relation of magnetic moment and the magnetic field of sample. During VSM shaker test process, the detection coil induced voltage need timely, synchronously recording and processing of the sample information. In fact, however, in order to obtain high signal-to-noise ratio, we must to integral signal (unlike the closed-circuit measurement of integral integrator) to obtain the average number, it usually takes 1 s or longer. Measured signal is more weaker, the longer the time required, the measured relative to the magnetic field changes of magnetic moment after the hysteresis effect is obvious.Getting the quality desander ? HERE TO FIND THE QUALITY ONES.
To solve this problem, we usually set the magnetic field to step change, after each step, the leap system needs to measure and calculate magnetic timely. History of VSM shaker was started in the above theory. In addition, in view of the nonlinear behavior of materials, each step along the hysteresis loop step change range of magnetic field should be the same, in order to obtain uniform magnetic moment of the resolution. Way to do this is using real-time feedback procedures; magnetic field intensity, measured by hall chip clearance compared with set values of magnetic field, and then uses the appropriate algorithm to get precise excitation current. Using VSM shaker as compared with those of closed-circuit measuring hysteresis loop measurement, because there is no zero drift problem, test process can last for a few minutes.Here you may also interested in VSM shaker , right?
Shortcoming is there is always a detecting coil near - samples and vibration rod sample; the biggest magnetic field of electromagnet gap is significantly lower than the closed circuit measurement. In order to improve the induction sensitivity, in the cases of saddle area, the coil can certainly as far as possible close to the position of the sample, so as to reduce gap. However, on the other hand, the distance of a first plane and the coil to the sample should not be too small, in order to reduce the effects of the mirror effect. The entire location of the organization of the samples came out to meet the magnetic field lines should be captured by detecting coil; it had better not be affected by mirror interference effect as far as possible. History of VSM shaker is long and tortuous.The featured decanter centrifuge can be find in our online website.
Most VSM shaker use electromagnet as field source, in the closed circuit measurement part we already mentioned the limitation of the scope of electromagnet for magnetic field strength, the problem for VSM shaker is more prominent. It is easy to understand, VSM shaker magnet pole head is put among the coil structure, it will inevitably increase the distance between the poles, so that the electromagnet maximum magnetic field will drop, and mirror effect will increase this trend. Usually, VSM shaker using electromagnet can produce about 2 t magnetic fields, and the same as loop measurement system, the magnetic field is not enough to completely characterize the magnetic properties of the rare earth permanent magnet high intrinsic coercive force. In order to obtain higher magnetic fields, are widely used in the VSM shaker system is superconducting solenoid coil, the device is relatively complex, because the device run-time needs continuous liquid helium cooling, its cost and maintenance cost is very high.You can find the best centrifugal pump in our store.