Development trends of ferrite materials and components in 21 century
With the development of information technology and digital electronics in 21st century, people put forward new demands on ferrite components, such as the miniaturization of devices, high-frequency, high-performance, low loss, and so on. In the next 10 years, people will focus on the development of high-frequency low-power, high-permeability materials and chip-based soft surface mount components, in the amorphous soft magnetic metal and magnetic recording materials, and the development of nano-materials. The 21st century is a development period for high-end products, and the market share of milled-low-end products will shrink gradually. Based on the world industrial development situation, we analyzed the prospect of the ferrite materials and components in the near future. Ferrite materials have been widely used in civilian and industrial areas in recent years. With the development of information technology and new green lighting, the features of the material head for high-frequency, high permeability and low-loss. There are three development features: miniaturization; chip-form; surface decoration:（1）the development of high-frequency. Ferrite power transformer used soft magnetic materials in the earlier time and with an increasing frequency of switching power supply, generation after generation of the material was developed. In the early 1970s, in order to meet the needs of the market, people developed the first-generation of power ferrite materials, such as TDK H35. This material because of its great power would only apply to work in the frequency of 20 kHz or so civilian power switch. In the early 1980s, the second-generation power ferrite materials were available, such as YDK H7C1 (PC30), this material has a negative temperature coefficient of power, with an increasing temperature, power consumption is declining, the operating frequency is about 100 kHz. In the late 1980s, in order to adapt to the development of high-frequency switching power supply, people developed a third generation power ferrite materials, such as TDK PC40, which operates at 250kHz, this type of material is particularly applicable to the work of a few hundred kHz frequency of Switching power supply, now widely used in industrial switching power supply. Into the mid-1990s, because of information technology on the miniaturization of devices and the chip-form requirements, the fourth generation of power ferrite materials has been developed successfully, such as the TDK PC50 material. The operating frequency of this material can be up to 500 kHz which provides more possibilities to manufacture better power switch with light, small, thin features. That is the development direction of ferrite materials. The soft ferrite materials industry standard newly released make the power ferrite materials divided into five categories PW1-PW5, and each category requires a higher operating frequency. the application of 15-100kHz frequency use PW1 materials; the application of 25-200kHz frequency use the PW2 materials; 100-300kHz frequency is PW3 material; 300kHz-1MHz is PW4 material; At present, domestic enterprises have been able to produce the equivalent of PW1-PW3 materials, Only some enterprises are trying a small production of PW4 material, PW5 material need further R&D （2）towards higher permeability; due to the rapid development of information industry, the traditional common ferrite can no longer meet the new requirements of information network technology, high-permeability material is an integral part used with the emerging IT technology. In addition, the application of electronic technology increasingly widespread, especially in digital circuit and switching power supply aspects and the problems caused by electromagnetic interference are becoming more serious. High permeability ferrite core can effectively absorb electromagnetic interference signals, in order to achieve the effect of anti-electromagnetic interference. With the electronics to high-frequency, high-speed, high-density development of the assembly to a variety of electronic, electrical wiring must be in core EMI, in order to meet the anti-electromagnetic interference and electromagnetic compatibility. The main characteristics of High permeability ferrite are particularly high permeability, generally more than 1,000, which can greatly reduce the core size, and likely to raise the operating frequency. At present many enterprises in our country can do the production in enormous quantities of magnetic conductivity 5000-7000 materials, even some enterprises are able to produce 10000 materials, but was bigger than 10000 materials also still to be in the development trial manufacturing the stage. At the same time, the high permeability of the core must be a very good surface quality must be uniform coating layer, dense, insulating organic coating, which is the product of a technical difficulty. (3) to the development of low-loss; in order to meet the high-definition television and computer monitor flyback transformers of the requirements of the development, as well as to the miniaturization of electronic transformers, high-frequency, low-loss development, low-loss ferrite materials, it is extremely Important. TDK in the early-middle 1990s use high-frequency low-power PC44 material to do the production of return transformers HV22 and HV38 materials and low-power switching power supply for the. The research of this material in China are still left far behind: （1）Inductance, trends coil of small, chip-based. Chip inductors are a electric components. The demand of inductors in world’s market is growing; in particular with the development of mobile communications at an alarming rate, the electromagnetic compatibility requires a large number of core, high-frequency anti-parasitic Oscillation core, the mixer used in the core, filter core, coupled with coil core, as well as a variety of chip inductors, and so on. At present, the hearing can be used in mobile-chip inductance, coil core, is about one-third of the market gap. In the chip inductors, laminated-chip inductors are now occupying mainstream status, its size has been reduced from 3216 (3.2X1.6mm) to narrow the current mainstream products, 1005 (1.0X0.5mm), this type of ultra-small inductors are widely used in communications devices and anti-electromagnetic interference (EMI) and electromagnetic compatibility (EMC) device. In the low-end applications, chip inductors may be replaced by bead-on-chip, so manufacturers have begun to integrate the production of thin-film capacitors have a chip inductors. In order to avoid such as switching power supply switching noise pollution, power networks, power input are set up ferrite input filter. Because the switching noise is a common mode signal, the current compensation can avoid a core principle of saturation, that is, in the non-magnetic system around two turns on the same series of reverse-coil, so that the load current magnetic field produced by offset, so that a total of Inductive impedance mode signals were blocked. Such filters are widely used in the use of high-frequency switching power supply of computers, program-controlled switches, power rectifiers and other fields. Chip inductors are now toward the direction of the development of high-frequency multi-layer models, such as in the 60GHz frequency of high-frequency multilayer chip inductors. At the same time, manufacturers are improving product of inductance, such as on-chip low-frequency electric power of the receptor from the amount of 33mH to 220mH; high-frequency electric sensor chip inductance from 180nH to 470nH.（2）The main electronic transformer to the small, lightweight, efficient, and surface-mount technology. As the micro-electronics technology, electronic equipment, greatly reducing the volume and weight; As a result, the requirements of electronic transformers have accordingly reduced the size and weight. Switching power supply, that is, using the power grid directly rectifier, since the early 1970s, the frequency of DC converter transformer switch has been advanced to 20 kHz, so as to replace the bulky transformer rectifier 50Hz. This revolutionary technology can enable electronic transformer can reduce the size of 3-5 times; reduce the weight of 3 times. Inductive Ni 50Hz transformer lights you use high-frequency electronic neon transformer work, reduce the size of about 1-2 times, to reduce the weight of about 4 times; more importantly, in line with the requirements of energy-saving green lighting project. With the high-frequency low-loss ferrite, switching power supply switching frequency from 20 kHz to 10MHz or so, so that the electronic transformer and weight can be further reduced. Therefore, the high-frequency electronic transformer leads to small and light development trend of electronic devices. A hopeless tangle of soft ferrite, the frequency must be addressed in more than 500 kHz with a smaller power loss. When the miniaturization of electronic transformers, commonly used surface mount technology, electronic transformer winding stacked with off-duty printing conductors, soft ferrite cores designed to be low and a high degree of magnetic thin film components. In telecommunication equipment and in digital network, to cause the transmission the simulated signal or the digital pulse signal is not obvious distortion, and request use of wide band signal impulse transformer. The low power wide band transformer's bandwidth and the magnetic conductivity are proportional, therefore the high magnetic conductivity soft magnetism ferrites widely use in the wide band pulse transformer. Along with the digit electronic installation integration degree's enhancement, the pulse transformer has become on the printed wiring board the biggest functional component, will become from now on one of main development directions. In recent years, the mobile phone, the notebook and digital instrument's development, caused the field to send shines the DC/DC power transformer to become a major new tendency. The micro-battery-voltage direct current to alternating voltage up to a certain value, added to the field to light-emitting film composed of parallel plate capacitors, so that the light-emitting chip luminescence. Program-controlled exchange of words frequency transformer is the domestic production of EP13 up to the high permeability core, the future size of the transformer will be out of a small core EP10 need to further enhance the permeability of the material. In the future, high-definition television monitors and high-frequency used in flyback transformers manufacturers will be the focus of product development. two-flyback transformers, high-rise flyback transformers will be more popular. In the future, R-ferrite core will replace the EI-core. Conclusion, Facing the 21st century, due to the change of industry structure, the electronic equipment and complementary components are improved with higher –performance feature.
Hope the ferroxcube materials can be used in production as equivalent to TDK FC40, PC44 and PC50 material, high permeability (10000-15000) material. Ferrite inductors and transformers are further miniaturized, and integrated with a chop-base thin form to meet the ever-changing information technology development.
All in all, in 21st century the magnetic products in the market will have a qualitative change. People will mainly use high-grade materials. After China enters into the WTO, the market will be of no national boundaries and we need to strengthen scientific technology and technological innovation, strengthen the technical transformation and management of enterprises. We need to do some adjustment of product structure and improve product quality to meet the new opportunities and challenges. It is believed that after China magnetic materials industry make the three strengthening points come true, China will be not only a big country in the production of magnetic materials but also become a powerful country in production of high-performance magnetic materials.