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Relationship between magnetic steel performance and motor performance

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 1. Influence of residual magnetism For a DC motor, under the same winding parameters and test conditions, the higher the remanence, the lower the no-load speed and the lower the no-load current; the greater the maximum torque, the higher the efficiency at the highest efficiency point. In the actual test, the level of no-load speed and the size of the maximum torque are generally used to judge the remanence standard of the magnetic steel. For the same winding parameters and electrical parameters, the running motor at a relatively low speed will generate enough reverse induced voltage to reduce the algebraic sum of the electromotive force applied to the winding. Therefore, the higher the remanence, the lower the no-load speed and the smaller the no-load current. Further Reading:  What Motors can be Used for NdFeB Magnets? 2. The influence of coercivity In the process of motor operation, there is always the influence of temperature and reverse demagnetization. From the p...
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ICP Atomic Emission Spectrometry Analysis of Chemical Composition of NdFeB Magnets

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Analysis Methods of NdFeB Magnets The chemical composition analysis of NdFeB Magnets  generally includes: 1- Chemical composition analysis of raw materials, including the chemical composition of rare earth metal raw materials, as well as the chemical composition of industrial pure Fe, B-Fe alloys and other metals, such as Ga, Al, Nb, Zr, etc.; 2- The chemical composition of the magnet. The analysis is required for unknown magnets or problems with magnets, not necessary if the product is of normal quality. The chemical composition of the magnet includes rare earth metal elements, such as Nd, Pr, Ce, Dy, Ho, Gd, Tb, etc., and other metal elements, such as Cu, Al, Nb, Zr, Ga, Co, Ti, etc.; 3- Content analysis of other non-metallic elements, such as hydrogen, oxygen, carbon and other elements content analysis. ICP emission spectroscopy is an analytical method that combines Inductively Coupled Plasma (ICP) and Atomic Emission Spectroscopy (AES). Principles of ICP The atoms or ions of th...
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Working Principles of Microwave Oven

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Magnetron Magnetron, also known as microwave generator and magnetron microwave tube, is a kind of electronic tube, mainly composed of two parts: tube core and magnet. The magnetron is the heart of the microwave oven. From the outside, it consists of a microwave transmitter (waveguide), a radiator, two pins of the filament, and a magnet. From the inside, there is a cylindrical cathode surrounded by an anode made of high-conductivity oxygen-free copper, which is used to receive electrons emitted by the cathode. Magnet The function of the magnet is to supply a strong magnetic field parallel to the axis of the anode. Generally, it adopts a simple structure and is made of  permanent magnets . Die The die consists of a filament, a cathode, an anode and a microwave energy exporter. Filament: The thorium tungsten wire or pure tungsten wire is wound into a spiral shape, and its function is to heat the cathode. Cathode: The cathode is made of a material with a strong ability to emit electr...
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Types of Magnets Used in Motors, Generators and Actuators

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Rare earth magnets (samarium cobalt and neodymium) or ferrite (ceramic) magnets can be used in magneto and automotive magnet applications. Rare earth magnets are usually 2 to 3 times stronger than ferrite or ceramic permanent magnets. In motors, this enables smaller and lighter motors with higher performance. Correspondingly, rare earth magnets are also more expensive than ferrite (ceramic) magnets. Samarium Cobalt Magnet Samarium Cobalt (SMCO) magnets were produced in the 1970s. Before NdFeB magnets, one of the advantages of using SmCo is that they are not easy to corrode and have better temperature resistance. This means that it can maintain its magnetic properties at extremely high or low temperatures. It is a good choice for applications with abnormally high or low temperatures. However, their power is slightly weaker than neodymium magnets. Its high magnetic strength, excellent temperature resistance and reliable performance without oxidation protection are ideal for high-temper...
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