Magnet Quality Measurement System

The DX-2012MQ rare earth permanent magnet material quality testing device uses a magnetic flux meter equipped with a one-dimensional Helmholtz coil, mainly used for measuring the magnetic flux of permanent magnet devices under the coil conditions. The magnetic moment of the device can be obtained by multiplying the coil constant. For samples with regular sizes, materials such as Br, Hcb, and BHmax can be calculated. Through experimental verification, the use of one-dimensional coils to test axially magnetized cylindrical, circular, and square rare earth permanent magnet samples can accurately test the total magnetic moment M (Mz, to be precise) of the material. By using the material BH demagnetization curve to approach a straight line, the three important parameters Br, Hcb, and BHmax of the material's magnetic properties can be accurately calculated to determine the quality of the material, It is well used in the transmission of rare earth permanent magnet material quality between material enterprises and material usage enterprises. The accuracy and repeatability of magnetic moment testing are far superior to using BH testing instruments to test standard sample transmission data. The testing efficiency is high, which can achieve full inspection of all magnetized samples and timely detection of device defects, while ensuring the judgment of material magnetic energy product level.

The DX-2012MQ rare earth permanent magnet material quality testing device uses a magnetic flux meter and Helmholtz coil to test the quality of rare earth materials, which has become a popular inspection method among enterprises. Although the magnetic properties of the testing material are not accurately measured by the permanent magnet material BH measurement device, and the intrinsic coercivity Hcj parameter of the material cannot be provided. However, due to its more reliable testing magnetic moment data and lower equipment costs, Suitable for all material manufacturing and communication between users, it will play a greater role in the field of magnetic measurement in the future.

Overall, the DX-2012MQ rare earth permanent magnet material quality testing device is a reliable and cost-effective solution for industry professionals who need to test the performance and quality of rare earth permanent magnet materials.

2.1Main tester machine:

2.2Helmholtz coil

Using two coils with identical radii and turns, coaxially arranging them with a spacing equal to the radius, this type of coil combination is called Helmholtz coils. It can generate weak magnetic fields up to hundreds of Gs; This coil has a large uniform area volume, wide usage space, and easy operation. It can achieve one-dimensional, two-dimensional, and three-dimensional combined magnetic fields, and can provide AC and DC magnetic fields. There is a good linear relationship between current and magnetic fields.

The DX-2012MQ rare earth permanent magnet material quality testing system consists of helmholtz coil and test host. Dexing company could customized the helmholtz coil according to the test sample size. Different sample size, different test coils. Dexing company lists the following models as your reference:

3.1Features

● Adopting a single-chip design, the program is automatically calculated, which is intuitive and convenient;

● Suitable for all rare earth permanent magnet materials, low equipment cost;

● It is convenient to measure the magnetic flux Ø and magnetic moment M of the material and calculate the data such as Br, Hcb and BHmax;

● It can measure rare earth samples of different sizes and is no longer limited by sample size;

● The non-magnetic heating ceramic furnace can be added, and the M-T curve of the rare earth permanent magnet is obtained by heating test;

● It can be used for rare earth permanent magnet materials for thermal stability and magnetic flux irreversible inspection;

● The fluxmeter uses low drift technology to make the test more stable and accurate.

3.2Application

Mainly used for measuring the magnetic flux of permanent magnet devices under the coil conditions, multiplied by the coil constant to obtain the magnetic moment of the device. For samples with regular sizes, materials such as Br, Hcb, and BHmax can be calculated.

4.1 SmCo28H sample size: L20mm×W10mm×5mm, the test data using DX-2012H permanent magnet material measuring device is as follows: Br=10.83kGs, Hcb=10.26kOe, Hcj≥30kOe, BHmax=27.78MGOe.
One-dimensional Helmholtz coil is configured with DX-2012MQ rare earth permanent magnet material quality test device (Permeability coefficient is calculated according to 1.05)

Comment: The test repeatability is excellent. The difference between the Br test accuracy and the BH test device is controlled within 0.6%, the magnetic permeability coefficient is calculated as 1.05 (accurate optimization can be performed), the Hcb deviation is within 1.56%, and the BH deviation is 1.04%.

4.2 . N30M sample size: D13.08mm×H6.35mm, the test data using DX-2012H permanent magnet material measuring device 

is as follows: Br=11.06kGs, Hcb=10.68kOe, BHmax=29.53MGOe.
One-dimensional Helmholtz coils (Permeability coefficient calculated according to 1.05) were constructed using the DX-2012MQ rare earth permanent magnet material quality tester:

The test repeatability is excellent. The accuracy of the Br test is 0.2% compared with the BH test device. The magnetic permeability coefficient is calculated according to 1.05 (accurate optimization can be performed), the Hcb deviation is within 1.55%, and the BH deviation is 1.75%.