Appearance Size and Physical Performance Testing:
| Testing items | Testing instruments | Testing indicators | Factors affecting indicators | Purpose of Testing |
| Size | Calipers, micrometers, pass and stop gauges, projectors, visual detectors | Length, width, thickness dimensions, verticality, parallelism, R angle, C angle, etc. | Machining equipment, testing tools, instrument accuracy, calibration employee skills, etc. | Ensure product assembly characteristics and quality performance consistency |
| Exterior | Visual observation, comparison card, tapping or developer, etc. | Pinholes, corners, scratches, cracks, etc. | Material formula, production process, machining process, etc. | Reduce product corrosion resistance, performance, mechanical failure risks, etc |
| Mechanical properties | mechanical testing machine, | Tension, compression, etc. | Material formula, production technology, machining technology, product specifications, etc. | Reduce the risk of product cracking during use |
| Coating bonding strength | Mechanical testing machine or cross-hatch testing | The degree and force of coating peeling, and the peeling ratio of cross-hatch areas | Electroplating pre-treatment and electroplating process, coating types | Ensure coating corrosion resistance |
| Corrosion resistance | test chamber | High-pressure accelerated aging test chamber | Electroplating process, coating, film thickness, environmental conditions, etc. | Reduce the risk of product corrosion in harsh environments |
Magnetic Performance Testing：
| Test items | Testing equipment | Detection Indicator | Factors affecting indicators | Testing purpose |
| Magnetic properties | Permanent magnet measuring instruments, such as the NIM series of Metrology Institute, Mianyang bipolar series, foreign Hirst, etc | Normal/high-temperature Br, Hcb, Hcj, Hk/Hcj, (BH)max, Br and Hcj temperature coefficient, inflection point, recovery permeability, etc. | Material formula, production process, processing accuracy, tester accuracy, test environment, etc. | Test various indicators of product performance to meet product usage requirements, etc. |
| surface magnetism | Surface magnetic distribution measuring instrument, Tesla meter, etc. | The size and distribution uniformity of surface magnetism in the center or specific area, etc. | Residual magnetism, product dimensions, measurement methods, etc. | Check the magnetic field size in local areas of the product's |
| magnetic moment | Magnetic moment tester, flux meter, etc. | Magnetic moment value | Residual magnetism, product size, etc. | More accurately reflects the magnetic properties of the product |
| Thermal demagnetization | Magnetic flux meter, oven, etc. | Magnetic flux, magnetic loss percentage | Material components such as Co, Nd, Gd, etc., product Pc value, Hcj, Hk/Hcj, etc. | More realistic magnetic stability of reaction products in high-temperature environments |
In terms of magnetic properties, in the early days, everyone focused on the two indicators of remanence Br and intrinsic coercive force Hcj. Now, more and more users are paying attention to magnetic moment and thermal demagnetization. We use magnetic steel mainly for its two important characteristics, one is the magnetic energy density per unit volume, and the other is the magnetic stability of high-temperature operation. It is more reasonable to use magnetic moment and thermal demagnetization to evaluate. Magnetic steel selected using thermal demagnetization indicators will undoubtedly have better service reliability and higher cost performance.
Auxiliary Testing Items
| Test items | Testing equipment | Detection Indicator | Factors affecting indicators | Testing purpose |
| Density | Solid density | Archimedean displacement method to calculate weight and mentioned ratios | Blank density | Material composition, sintering process, preparation process |
| Carbon and sulfur content | Infrared carbon and sulfur analyzer | The high temperature causes the carbon and sulfur in the sample to burn to form oxides for detection. | C, S content | Raw material preparation process |
| Oxygen, nitrogen, and hydrogen content | Oxygen, nitrogen, and hydrogen tester | The sample is converted at high temperatures to produce co, CO2, N2, and H2 for detection. | O, N, H content | Raw material preparation process |
| Element | Plasma emission spectrometer | Atoms transition after ionization and detect the released electromagnetic wave energy, which corresponds to elements with different characteristic spectra. | Such as Pr, Nd, Fe, Cu, B, and other elements | Formula design, raw material composition, production process, testing accuracy |
| Microscopic | Scanning electron microscope, energy spectrometer | Analyze the surface characteristics of the sample through secondary electrons, scattered electrons, and characteristic X-ray signals | Grain appearance, morphology, and size, microscopic composition | ample preparation, electron microscope resolution, and accuracy |