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Permanent Magnets: More Than Just a “Magnet“

In daily life, we are no strangers to magnets. The iron – absorbing stones we played with as children are the most common permanent magnets. However, permanent magnets in modern technology are no longer simple “iron – absorbing stones”. As a material that can generate a lasting magnetic field, they play an indispensable role in many key fields. From new energy vehicles to wind power generation, from electronic devices to the medical field, permanent magnets are everywhere, promoting the progress of science and technology and the development of industries.

Unique Advantages of Permanent Magnets

Permanent magnets can play a significant role in many fields thanks to their series of unique physical properties. These properties not only determine the performance of permanent magnets but also lay a solid foundation for their wide application.

High Coercivity, the Basis of Stability

Coercivity is the reverse magnetic field strength required to reduce the magnetic induction intensity of a magnetized permanent magnet to zero. High coercivity means that permanent magnets are not easy to lose their magnetism when subjected to external magnetic field interference or mechanical vibration, and can stably maintain their own magnetic field characteristics. Take the drive motor of new energy vehicles as an example. During the driving process of the car, the permanent magnets inside the motor not only have to bear the mechanical stress generated by high – speed rotation but also deal with the complex electromagnetic environment. However, due to the high coercivity of permanent magnets, the motor can run stably, ensuring the power output of the car. This characteristic enables permanent magnets to work normally in complex environments, ensuring the stability and reliability of related equipment.

High Remanence, the Source of Magnetic Field

Remanence refers to the magnetic induction intensity retained by a permanent magnet when the external magnetic field is removed. High remanence enables permanent magnets to generate a strong magnetic field, providing a basis for their role in many application scenarios. In the field of wind power generation, permanent magnet direct – drive generators use the high remanence characteristic of permanent magnets to generate a stable magnetic field, efficiently converting wind energy into electrical energy. A stronger magnetic field can improve the efficiency and power density of the generator, making wind power generation more efficient and economical.

Diverse Curie Temperatures, Adapting to Different Environments

The Curie temperature is the critical temperature at which a permanent magnet loses its magnetism. Permanent magnets made of different materials have different Curie temperatures. In practical applications, it is necessary to select permanent magnets with an appropriate Curie temperature according to the specific working environment to ensure that they can work normally within the corresponding temperature range. For example, industrial equipment working in a high – temperature environment, such as magnetic components in high – temperature furnaces, needs to use permanent magnets with a high Curie temperature; while in general electronic equipment, the requirement for the Curie temperature is relatively low, and more economical permanent magnet materials can be selected.

Wide Applications of Permanent Magnets

With their unique performance advantages, permanent magnets play a key role in many fields and have become an indispensable part of modern technology. From daily – used electronic devices to wind power generation related to energy transformation, from high – speed and convenient transportation systems to precision medical equipment, permanent magnets play a pivotal role.

Electronic Field: The Unsung Hero of Sound and Data

In the electronic field, permanent magnets are everywhere, especially in audio equipment such as speakers and headphones. Take the speaker as an example. When the audio current passes through the voice coil, the voice coil is subjected to the Ampere force in the magnetic field generated by the permanent magnet, thus driving the diaphragm connected to the voice coil to vibrate, and then pushing the air to produce the sound we hear. The stable magnetic field generated by the permanent magnet is the key to ensuring the smooth progress of this process, which makes the sound reproduction more accurate and the sound quality clearer and fuller. Whether it is the shocking sound effect in the home theater or the delicate music in the headphones, it is inseparable from the contribution of permanent magnets.

Permanent magnets also play an important role in hard disk drives. The voice coil motor (VCM) is one of the key components of the hard disk drive. It uses the interaction between the magnetic field generated by the permanent magnet and the energized coil to realize the fast and accurate movement of the magnetic head, thereby completing the reading and writing of data. With the continuous growth of data storage demand, the requirements for hard disk storage density and read – write speed are getting higher and higher. Relying on its characteristics of high coercivity and high remanence, permanent magnets can provide a strong and stable magnetic field for the voice coil motor, enabling the magnetic head to locate the data storage position more quickly and accurately, which greatly improves the data storage density and read – write speed of the hard disk and meets people’s needs for large – data storage and fast access.

Energy Field: The Core Power of Wind Power Generation

In the context of the global active promotion of clean energy development, wind power generation, as an important way of using renewable energy, is being applied more and more widely. The permanent magnet direct – drive wind generator is a key equipment in the field of wind power generation, and the permanent magnet is its core component.

The working principle of the permanent magnet direct – drive wind generator is based on the law of electromagnetic induction. When the wind blows the wind wheel to rotate, the wind wheel drives the generator rotor directly connected to it to rotate synchronously, and the permanent magnets on the rotor rotate accordingly to generate a rotating magnetic field. The stator windings cut the magnetic lines of force under the action of this rotating magnetic field, thus generating an induced electromotive force, realizing the direct conversion from mechanical energy to electrical energy. Compared with the traditional doubly – fed wind generator, the permanent magnet direct – drive wind generator omits the gearbox as an intermediate component, reduces the mechanical loss in the energy conversion link, and improves the power generation efficiency.

The application of permanent magnets in permanent magnet direct – drive wind generators not only improves the power generation efficiency but also enhances the reliability and stability of the generator. Because there is no gearbox, the problems such as oil leakage, wear, and failure that may occur in the gearbox are avoided, the maintenance cost and downtime are reduced, and the wind power generation system can operate more stably. The high coercivity and high remanence characteristics of permanent magnets ensure that the generator can produce stable electric energy output under different wind speed conditions, provide reliable power support for the power grid, and effectively promote the development of clean energy.

Transportation Field: The Suspension Mystery of Maglev Trains

As an advanced rail transit tool, maglev trains have become a bright star in the field of modern transportation with their advantages of high speed, stability, and low noise. Permanent magnets play a vital role in the operation of maglev trains and are the key factors for realizing the suspension and high – speed operation of the trains.

Maglev trains mainly use the principle of (like poles repel) of permanent magnets. Permanent magnets are installed on the bottom of the train and the track respectively. When the train is running, the like magnetic fields generated by the permanent magnets at the bottom of the train and those on the track repel each other, so that the train is suspended above the track, with almost no mechanical contact between the train and the track, which greatly reduces the friction during operation. This non – contact operation mode enables maglev trains to run at an extremely high speed, with a maximum speed of hundreds of kilometers per hour, and also reduces energy consumption and noise pollution.

In addition to realizing suspension, permanent magnets also play an important role in the guidance and drive systems of maglev trains. Through the reasonable design of the layout and magnetic field distribution of permanent magnets, the precise control of the running direction of the train can be realized, ensuring the stability and safety of the train during high – speed operation. In terms of driving, the electromagnetic force is used to enable the train to accelerate and decelerate quickly on the track, realizing efficient transportation. The application of permanent magnets makes maglev trains an efficient, environmentally friendly, and comfortable modern transportation mode, providing a new solution for fast transportation between cities and regions.

Medical Equipment: A Powerful Assistant for Accurate Diagnosis

In the medical field, permanent magnets provide a stable magnetic field for high – precision medical imaging diagnosis, helping doctors accurately judge the condition and safeguarding patients’ health. Among them, magnetic resonance imaging (MRI) equipment is a typical representative of the application of permanent magnets.

MRI equipment uses a strong magnetic field and radio frequency pulses to image the internal tissues of the human body, which can clearly show the structure and lesions of various organs and tissues of the human body, providing an accurate diagnostic basis for doctors. Permanent magnets play a key role in generating a stable magnetic field in MRI equipment, and their high magnetic field strength and uniformity are important prerequisites for ensuring imaging quality. Through the carefully designed and manufactured permanent magnet system, a highly uniform static magnetic field can be generated in the imaging area, so that the hydrogen nuclei in human tissues resonate under the action of the magnetic field, generating magnetic resonance signals. These signals are collected, processed, and reconstructed to finally form high – resolution medical images, helping doctors detect early lesions and formulate precise treatment plans.

Compared with other imaging technologies, MRI has the advantages of no radiation, high soft tissue resolution, and multi – orientation imaging, and has important application value in the diagnosis of the nervous system, cardiovascular system, and tumors. The continuous development and innovation of permanent magnets have made it possible for MRI equipment to be miniaturized, lightweight, low – power consumption, and have higher imaging performance, enabling MRI technology to be more widely used in clinical diagnosis and medical research, and making greater contributions to the cause of human health.

Hangzhou Magnet Power Technology Co., Ltd.: Expert in Permanent Magnet Solutions

Hangzhou Magnet Power Technology Co., Ltd., founded by a team of doctors from the Chinese Academy of Sciences, is a high – tech enterprise specializing in the research and development, production, and sales of high – end rare earth permanent magnet materials and devices. Since its establishment, the company has always adhered to the development concept of innovation – driven and quality first, continuously deepened its research in the field of permanent magnets, and is committed to providing high – quality permanent magnet products and professional solutions for global customers. With its excellent technical strength and persistent pursuit of quality, the company has quickly emerged in the industry and won wide recognition and trust.

Our Products and Services

The company provides a variety of permanent magnet products, including high – performance samarium – cobalt permanent magnets and high – performance neodymium – iron – boron permanent magnets. Samarium – cobalt permanent magnets have high coercivity, high working temperature, and good chemical stability, and are suitable for harsh environments such as high temperature and strong corrosion, such as aerospace and high – end motors; neodymium – iron – boron permanent magnets, with their characteristics of high remanence and high magnetic energy product, are widely used in electronic devices, new energy vehicles and other fields. In addition to standard products, the company also provides customized services, tailoring permanent magnet solutions according to customers’ special needs to meet the diversified needs of different industries and application scenarios.

Quality Inspection and Control

Hangzhou Magnet Power Technology Co., Ltd. has always regarded product quality as the lifeline of the enterprise and has established a perfect quality inspection and control system. Every link from raw material procurement to product production strictly follows international standards and industry norms to ensure that every permanent magnet product leaving the factory has excellent performance and reliable quality.

In the raw material procurement link, the company has established long – term and stable cooperative relations with high – quality suppliers at home and abroad. Each batch of raw materials is strictly inspected and screened to ensure that their chemical composition, physical properties, and other indicators meet the product design requirements, thus ensuring product quality from the source.

In the production link, the company has introduced internationally advanced production equipment and automated production lines, and at the same time adopted advanced production processes and technologies to monitor the production process and collect data throughout the process, grasp the production status in real – time, adjust production parameters in a timely manner, and ensure the stability and consistency of product quality. The company also pays attention to the management of the production environment, strictly controls environmental factors such as temperature, humidity, and cleanliness in the production workshop, and provides good production conditions for product quality.

In terms of product quality testing, the company is equipped with a professional testing laboratory and advanced testing equipment, such as magnetic property testers, metallographic microscopes, and spectrum analyzers, which can comprehensively and accurately test and analyze the magnetic properties, physical properties, chemical composition, and microstructure of permanent magnets. The company has formulated strict quality testing standards and processes, with quality inspection points set for each process. Products are strictly inspected, and only products that pass the inspection can enter the next process, ensuring that each product leaving the factory meets high – quality standards.

Application Cases

In the field of new energy vehicles, the high – performance neodymium – iron – boron permanent magnets provided by Hangzhou Magnet Power for a well – known new energy vehicle brand are applied to its drive motors, which effectively improve the efficiency and power density of the motors and significantly increase the cruising range of the vehicles. The automobile brand reported that after using Cijuli’s permanent magnets, the performance of the motor is more stable, the noise and vibration are significantly reduced, and the overall performance and user experience of the vehicle have been greatly improved.

In the field of medical equipment, the permanent magnets provided by the company for a medical equipment manufacturer are used in magnetic resonance imaging (MRI) equipment. The customer said that the magnetic field generated by Cijuli’s permanent magnets has high uniformity and clear imaging quality, which helps doctors diagnose the condition more accurately, improves the accuracy and reliability of medical diagnosis, and has been highly praised by medical institutions and patients.

Customize Exclusive Magnets

If you are looking for a partner to customize exclusive magnets, Hangzhou Magnet Power Technology Co., Ltd. will be your best choice. We have a professional R & D team and advanced production equipment, and can tailor various high – performance permanent magnet products for you according to your unique needs. Whether you need permanent magnets of special shapes and sizes, or have special requirements for magnetic properties and working temperature, we are confident to provide you with satisfactory solutions. From product design, R & D to production and testing, we will provide you with professional services and technical support throughout the process to ensure the smooth implementation of your customized magnet project. Choosing Cijuli means choosing high – quality and high – performance customized magnets. Let us work together to create a better future.