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How waste-to-energy incineration works

Waste-to-energy plants use household garbage as a fuel for generating power, much like other power stations use coal, oil or natural gas.Regarding garbage incineration, the first thing to note is that not all garbage can be burned. In general, garbage incineration is the burning of organic components in waste. For example, municipal solid waste represented by various domestic wastes including kitchen waste can kill toxic and harmful components through incineration, and greatly reduce the volume of waste. It can also be used, and the landfill after burning saves space. The calorific value released during combustion can also be used to generate electricity and heat, and become a waste-to-energy source. The biggest concern of environmentalists and the public about waste incineration comes from the emission of toxic substances such as dioxins and furans during the incineration process. In the last century, the old-fashioned incinerators of various countries did not pass the gas purification technology, and this problem did exist. Since the end of the last century, many countries have improved gas purification technology and hardware, and the situation has improved greatly.  Waste-to-Energy: How It WorksWaste material is received in an enclosed receiving area, where it is thoroughly mixed in preparation for combustion.The mixed waste enters the combustion chamber through the grate that moves regularly, and the grate splashes and burns at the same time.The particles in the air are removed in the filter bag.The acidic combustion gas is neutralized by injecting lime or sodium hydroxide.Acid combustion gas injection lime or sodium hydroxide to neutralize. The unburned residue from the combustion is removed by magnets and eddy current separators to remove iron and other metals such as copper, brass, nickel and aluminum for recycling.The unburned residue from the combustion is removed by magnets and eddy current separators to remove iron and other metals such as copper, brass, nickel and aluminum for recycling.Combustion of unburned residues, remove iron and other metals, such as copper, brass, nickel and aluminum by a magnet and the vortex separator for recycling.The remaining ash can be used as aggregate for roadbeds and railway embankments. Superheated steam powers the steam turbine generator. The cooling steam is cycled back into water through the condensor or diverted as a heat source for buildings or industry. Cooled stream is reheated in the economiser and superheater to complete the steam cycle.

Why was there more matter than antimatter in the Universe?

13.8 billion years ago, shortly after the Big Bang, the universe expanded rapidly and a large amount of energy was converted into matter.Physicists speculate that this process initially produced equal amounts of matter and antimatter, which would be annihilated once they contacted.But then an unknown event was sent, making matter more than antimatter, and then forming all the things we can see and touch.Studies have shown that the clues of the event may be hidden in tiny ripples in time and space.But in fact, the universe has evolved for tens of billions of years and continues to exist today. Obviously, not all matter was annihilated at the beginning. The answer to this question may also involve a very strange elementary particle-neutrinos.The neutrino is not charged, and its antiparticle may be itself.One view is that about 1 million years after the Big Bang, the universe underwent a phase change as it cooled.Droll said: "This disguise may cause neutrinos to produce slightly more matter than antimatter when decayed. But there is no easy way to verify whether this event has actually happened in the universe. But the Droll team found a way through modeling and calculations that might be able to show us this disguised process. They proposed that the phase transition may produce an extremely slender energy line, which is still permeating the universe to this day.These cosmic rays are very likely to cause tiny ripples in space and time, that is, gravitational waves.As long as the corresponding gravitational waves are detected, the correctness of this theory can be verified.

What's tip effect and how it affects on coating?

Corona discharge is a process in which electric current flows from a charged object (electrode) to an uncharged fluid, thereby causing the generation of ionic molecules near the electrode. The tip discharge refers specifically to the corona discharge phenomenon caused by sharp objects in corona discharge. In coating industry, we also call it tip effect or bone effect. How does the tip effect affect electroplating?Answer: When the process does not conform to the standard.The tip effect tends to cause thickening, burrs, or scorching of the coating on the tip or edge of the product. Therefore, we should try to eliminate or control the impact of tip effect to ensure product quality.  How to reduce or eliminate the tip effect, in actual operation, different measures should be taken according to different situations: control the current density; adjust the composition of the plating solution; add appropriate additives;change the pH value of the plating solution; add auxiliary poles to the workpiece; adjust the distance between cathode and anode; change the geometry of the anode and the electroplating bath; change the suspension mode and position of the workpiece, etc.

What is meant by ippc in a wooden pallet?

IPPC is an international convention. The IPPC logo on the wooden packaging means that it has been treated and qualified in accordance with the regulations and does not carry harmful organisms.They developed a standard for wood packaging in international business, called ISPM-15.It looks like this:                               What is covered by this global standard?Some wood packaging production processes have reached the conditions of pesticide treatment, no longer need to carry out special pesticide treatment.For example, wooden cases and wooden pallets made entirely of plywood, particleboard, fiberboard and other artificial panels.Or made entirely of thin board (including wood shavings, wood chips, etc.) with a thickness less than 6mm.     Wood packaging processed in the production process, such as wine barrels, wooden gift boxes, etc,They also don't need to be fumigated。  In addition to the above, all wood packaging containing solid wood components must be treated in accordance with the regulations, and the standard IPPC mark, such as the following wood package:    How to add the IPPC mark to the wooden case of goods?Only with the enterprises that have obtained the customs permission to apply the label on the wooden packaging of outbound goods can produce and apply the IPPC mark on the wooden package of outbound goods.The enterprises using wood packaging can purchase wood packaging from the qualified labeling and applying enterprises, and require the labeling and applying enterprises to provide the certificate of qualified wood packaging disinfection and disinfestation treatment for outbound goods.Improper handling of inbound and outbound wood packaging may lead to the spread, diffusion and colonization of pests during international transportation.If the exported goods are packaged in natural wood packaging, IPPC should be added according to the destination country of the export. For example, if the packaged goods exported to the European Union, the United States, Canada, Japan, Australia and other countries are packaged in conifer wood, they must be fumigated.For fumigation, it is now standardized that the fumigation team will fumigate the container according to the container number, that is, after the goods arrive at the site, the professional fumigation team will stamp the IPPC mark on the package.

Magnetic Particle Testing

Magnetic Particle TestingMagnetic particle inspection is also known as MT or MPT, which is suitable for inspection methods near the surface of magnetic materials such as steel.Use the principle that iron is attracted by magnets for inspection.During the magnetic particle inspection, the object to be tested receives the action of magnetic force, and the magnetic powder (magnetic micro powder) is scattered on its surface.Then, the leaking magnetic force leaking out of the defective part of the surface will attract the magnetic powder to form an indication pattern. The indicator pattern is dozens of times larger than the actual defect, so it is easy to find the defect.Magnetic particles are applied to the surface of the specimen. The specimen is then magnetised. If flaws are present the magnetic particles form anarrangement around the fault. This method is used on magnetic materials such as steels and cast irons. Magnetic particles can detect defects up to 18 mm below the surface of a weld.Magnetic particle inspection method1,Pre-treatmentIf grease, paint, rust, or other foreign matter adheres to the flaw detection surface, it will not only prevent the magnetic powder from being adsorbed on the scar, but also cause the magnetic powder to adsorb to the part other than the scar to form a suspicious image.Therefore, before magnetization, a physical or chemical treatment is used to remove dirt and foreign matter.2,MagnetizationIt is very important to magnetize the test object properly.Usually, a magnetization method perpendicular to the direction of the scar and the direction of the magnetic force line is used.In addition, for proper magnetization, various methods can be used according to the shape of the object to be detected.3,Use of magnetic powderIn order for the magnetic powder to be adsorbed between the magnetic poles of the scar to form a detected image, the magnetic powder used must be easily magnetized by the weak magnetic field of the scar and adsorb to the magnetic poles, that is, a certain adsorption performance is required.In addition, it is required that the magnetic powder image formed must have a high degree of recognition.Generally, the magnetic powder used in magnetic particle inspection includes white, black, red and other different magnetic powders used under visible light, and fluorescent magnetic powders that use fluorescent light.In addition, depending on where the magnetic powder is used, there are powdery dry magnetic powder and wet magnetic powder dispersed in water or oil.4,ObservationTo observe the magnetic particle image attached to the scar, it is necessary to create an easy-to-observe environment.Ordinary magnetic powder needs to be observed in the brightest possible environment, while fluorescent magnetic powder needs to use ultraviolet light to make the surroundings as dark as possible to be easy to observe.

What is HK

We all know that the four parameters Br/Hcb/Hcj/Bhmax are the main parameters of magnet material performance. The engineer of magnet application design selects the appropriate magnetic material according to the electromagnetic conversion corresponding to these parameters. After the magnet is prepared, we can obtain these parameters by testing the demagnetization curve, and there are some other parameters on the demagnetization curve that are also very important for the application of the magnet, such as HK.The second quadrant of the demagnetization curve is the commonly used J-H curve, which is the correlation curve between the magnet's magnetic polarization intensity J and the external magnetic field intensity H, which can reflect the changes in the internal magnetic properties of the magnet. When the magnetic polarization intensity J on the J-H curve is 0, the corresponding magnetic field intensity is called the intrinsic coercivity Hcj. The value of intrinsic coercivity reflects the size of the anti-demagnetization ability of the permanent magnet material. From the J-H graph, we can find that when the external magnetic field keeps increasing, the magnetic induction intensity/magnetic polarization intensity of the magnet decreases very slowly, but when the external magnetic field is greater than a certain value, the magnetic induction intensity of the magnet decreases rapidly. We reduce this by 10% (or 5%) of the magnet’s magnetization, which requires the application of a reverse magnetic field, called Knee coercive force, which is HK. After the external magnetic field exceeds the tolerance of HK, it will cause a large Irreversible magnetic loss, magnet application designers are very concerned about this point. Usually we can see the ratio of HK/Hcj from the demagnetization curve. This ratio is called squareness. Generally, we consider magnets with squareness greater than 90% to be qualified. Hk/Hcj is also one of the important magnetic properties of permanent magnets. Like μrec, it characterizes the stability of the magnet under dynamic working conditions. HK/Hcj=1/μrec, the squareness is inversely related to the magnet's recovery permeability μrec. The larger the HK/Hcj, the closer the recovery permeability μrec is to 1, and the material's ability to resist interference from external magnetic fields and environmental temperature factors is better. The stronger, the better its stability. Therefore, increasing HK has greater practical significance for high-temperature applications such as motors.

How to choose the EV (electric vehicle) motor

The performance of the drive motor directly determines the performance of the drive system. In electric vehicles, the selection principles of electric motors are as follers. (1) High performance, low weight, and small size;(2) Higher efficiency in a wider speed range;(3) The electromagnetic radiation is as small as possible;(4) Low cost. In addition, the selection of the motor must also consider the characteristics of its control system, which can realize two-way control and recover braking regenerative energy. From the perspective of development trends, traditional DC motors will lose their competitiveness, and the application of switched reluctance motors and permanent magnet hybrid motors in electric vehicles has development potential. The DC motor drive system has the advantages of low cost, easy smooth speed regulation, simple controller, mature technology, etc., and is widely used in electric vehicles. The disadvantages of DC motors are lower efficiency than asynchronous motors, large size and mass, inconvenient maintenance of brushes and commutators, and commutation limits the speed of the motor (the maximum speed is between 6000r/min and 8000r/min). It is only a three-phase AC motor. Half of the maximum speed, or even lower. Compared with DC motors, asynchronous motors have the characteristics of high efficiency, simple structure, sturdy, maintenance-free, small size, and light weight, so they have broad application prospects. However, its control system is more complicated, the vector control technology requires high frequency conversion speed regulation, and the cost of using high-power semiconductor devices and microprocessors is relatively expensive. However, due to its light weight, high efficiency, and more effective realization of regenerative braking, it is The operating cost is lower than that of the DC motor drive system. With the reduction of cost and the improvement of reliability, the permanent magnet synchronous motor drive system will be used in a certain range of electric vehicles. Its efficiency can reach 97%, the smallest volume, the lightest weight, and the commutator without DC motor. The shortcomings of electric brushes, but there are still shortcomings such as high cost, reliability and service life worse than asynchronous motors. Switched reluctance motor is a new type of motor. Its structure is simpler than that of any kind of motor. Its efficiency can reach 85% to 93%. Its speed can reach 15000r/min. Its torque-speed characteristics are better. Within the range, the torque and speed can be flexibly controlled, and it has the characteristics of high starting torque and low starting power, but the torque ripple is large during operation, the noise is also large, and the volume is larger than the asynchronous motor of the same power. As the power system of the three major parts of electric vehicles, the importance of electric motors is self-evident. With the development of motor research and development technology, motors that are more suitable for electric vehicles will appear in the future. Let's share it again at that time.

How to choose the EV (electric vehicle) driving motors

The performance of the drive motor directly determines the performance of the drive system. In electric vehicles, the selection principles of electric motors are as follers. (1) High performance, low weight, and small size; (2) Higher efficiency in a wider speed range; (3) The electromagnetic radiation is as small as possible; (4) Low cost. In addition, the selection of the motor must also consider the characteristics of its control system, which can realize two-way control and recover braking regenerative energy. From the perspective of development trends, traditional DC motors will lose their competitiveness, and the application of switched reluctance motors and permanent magnet hybrid motors in electric vehicles has development potential. The DC motor drive system has the advantages of low cost, easy smooth speed regulation, simple controller, mature technology, etc., and is widely used in electric vehicles. The disadvantages of DC motors are lower efficiency than asynchronous motors, large size and mass, inconvenient maintenance of brushes and commutators, and commutation limits the speed of the motor (the maximum speed is between 6000r/min and 8000r/min). It is only a three-phase AC motor. Half of the maximum speed, or even lower. Compared with DC motors, asynchronous motors have the characteristics of high efficiency, simple structure, sturdy, maintenance-free, small size, and light weight, so they have broad application prospects. However, its control system is more complicated, the vector control technology requires high frequency conversion speed regulation, and the cost of using high-power semiconductor devices and microprocessors is relatively expensive. However, due to its light weight, high efficiency, and more effective realization of regenerative braking, it is The operating cost is lower than that of the DC motor drive system. With the reduction of cost and the improvement of reliability, the permanent magnet synchronous motor drive system will be used in a certain range of electric vehicles. Its efficiency can reach 97%, the smallest volume, the lightest weight, and the commutator without DC motor. The shortcomings of electric brushes, but there are still shortcomings such as high cost, reliability and service life worse than asynchronous motors. Switched reluctance motor is a new type of motor. Its structure is simpler than that of any kind of motor. Its efficiency can reach 85% to 93%. Its speed can reach 15000r/min. Its torque-speed characteristics are better. Within the range, the torque and speed can be flexibly controlled, and it has the characteristics of high starting torque and low starting power, but the torque ripple is large during operation, the noise is also large, and the volume is larger than the asynchronous motor of the same power. As the power system of the three major parts of electric vehicles, the importance of electric motors is self-evident. With the development of motor research and development technology, motors that are more suitable for electric vehicles will appear in the future. Let's share it again at that time.

The function of rare earth elements in NdFeB

Sintered NdFeB, as the name implies, is an alloy material composed of Nd2Fe14B, a compound composed of three elements: Nd, Fe, and B. However, sintered NdFeB is not a single phase. It consists of Nd2Fe14B phase and B-rich phase (also known as Nd1 .1Fe4B4 phase) and Nd-rich phase (also known as rare-earth-rich phase), of which the Nd2Fe14B phase is the main phase or basic term. Most rare earth elements (RE) form RE 2Fe14B compounds, which are the basic phase of sintered rare earth iron boron permanent magnet materials, accounting for 96%-98% of sintered rare earth iron boron permanent magnets. All RE 2Fe14B compounds have the same crystal structure, but their magnetic properties are very different. Adding other rare earth elements to sintered NdFeB to replace neodymium can change some properties of the magnet. The role of heavy rare earth metal Dy instead of Nd 1. Significantly improve the coercivity of the magnet The anisotropy field HA of Dy 2Fe14B compound is about 2.14 times higher than that of Nd2Fe14B, so replacing Nd with a small amount of Dy can significantly increase the coercive force Hcj of the magnet. Theoretically, every time 1% (atomic fraction) Dy replaces Nd, the coercive force Hcj of the magnet can be increased by 11.4kA/m, but the increase in coercive force Hcj in practical applications is related to the existence of other components. 2. Reduce the magnetic polarization intensity Js of the magnet Thereby reducing the remanence Br and the maximum magnetic energy product (BH) m In theory, every time 1% (atomic fraction) Dy replaces Nd, the magnet's magnetic polarization intensity Js decreases by 90mT 3. Reduce the temperature coefficient of magnet remanence Br and maximum magnetic energy product (BH) m It should be noted that the addition of heavy rare earth element Dy will significantly increase the raw material cost of sintered NdFeB permanent magnets, so the relationship between cost and magnet performance needs to be comprehensively considered. The role of heavy rare earth metal Tb instead of Nd Adding Tb to the sintered NdFeB magnet to partially replace Nd has the same effect as the replacement of Nd by Dy, but the anisotropic field HA of Tb 2Fe14B is higher, so it can more effectively improve the coercivity of the permanent magnet. But Tb has less reserves in rare earth mines than Dy, and the price is higher. The role of metal Gd and metal Ho replacing Nd Among the heavy rare earth metals, Gd has the highest reserves, and Gd can also form Gd2Fe14B compounds. The magnetic polarization intensity Js and anisotropic field HA of this compound are obviously lower, but its Curie temperature Tc is the highest. Due to the high reserves of Gd and the low price, some manufacturers add Gd in the form of gadolinium-iron alloy to partially replace Nd to produce low-cost sintered NdFeB. However, its practical use of Gd to replace Nd is a waste. Once it is discovered that Gd has more important uses in the future, it will be found to be an irreversible loss. Replacing Nd with Ho has the same effect and problem. The role of light rare earth metals La, Ce, Pr instead of Nd The reserves of light rare earth elements are abundant and the price is relatively cheap. The development of light rare earth metals for the manufacture of sintered NdFeB materials is worth encouraging. La, Fe, and B metals are difficult to form La2Fe14B, and the temperature is very narrow, but once formed, it is stable below 860°C. Nd accounts for 65%-75% of the cost of sintered NdFeB. At this stage, the cost of La is about one-tenth of Nd. Substituting La for Nd can reduce costs and promote the comprehensive utilization of rare earth resources. With the increase of La content, the magnetic polarization intensity Js, remanence Br, coercive force Hcj and maximum magnetic energy product (BH) m of the alloy will all decrease. La is a non-magnetic atom. Because of magnetic dilution, (BH)m decreases It decreases much faster than Br. Ce2Fe14B has poor stability and is more difficult to form. With the increase of Ce content, various magnetic properties are reduced. At the same time, the addition of Ce will cause the Curie temperature and temperature stability of the magnet to decrease. The Pr2Fe14B compound has several basic conditions that can be used as a permanent magnetic material. It can be sintered at about 1060°C to obtain better magnetic properties. Using (PrNd)-Fe metal as a raw material can produce sintered NdFeB permanent magnets with good magnetic properties. It should be noted that Pr is easier to oxidize than Nd, and the amount of Pr must be appropriately controlled for some materials that require high stability. The role of other metals replacing Fe The low coercivity and Curie temperature of sintered NdFeB permanent magnet material, poor temperature stability, low working temperature (about 80℃), poor corrosion resistance and other shortcomings limit its application range. For this reason, people the effects of various elements on NdFeB permanent magnet materials have been extensively studied. 1. The effect of cobalt-Co partial substitution of Fe on sintered NdFeB With the increase of Co content, the Curie temperature of the alloy increases linearly, and the reversible temperature coefficient of magnetic induction decreases significantly. When the Co content is less than 5% (atomic fraction), (BH) m and Br hardly decrease; when the Co content is more than 30%, the magnetic performance parameters are significantly reduced. The added Co content of less than 10% is very beneficial, which not only increases the Curie temperature of the alloy, but also maintains higher magnetic properties, and at the same time the temperature coefficient of magnetic induction is also improved. 2. The role of Al partly replacing Fe The research results of scholars show that adding a small amount of aluminum Al can significantly increase the coercivity of the ternary Nd-Fe-B material. The research results point out that since the Nd-Fe-Co-B permanent magnet material, the addition of Al can compensate for the decrease in coercivity caused by the addition of Co, so that a Nd-Fe-Co-Al- with higher comprehensive performance can be obtained. B alloy. 3. The role of Cu partially replacing Fe pair Studies have found that adding a small amount of copper to the (Nd, Dy)-Fe-B and (Nd, Dy)- (Fe, Co)-B systems can significantly increase the coercivity, while Br hardly decreases, so that permanent magnets with high Hcj and high (BH)m can be manufactured. 4. Partial replacement of Fe by other elements Based on ternary Nd-Fe-B alloy, adding a small amount of niobium Nb or zirconium Zr to replace part of the iron can effectively increase the Hcj and squareness Hk of the alloy, while the Br is reduced very little, and the magnetic flux of the alloy cannot be reduced. loss. The experimental results show that the maximum content of niobium and Nb in Nd-Fe-B alloy is 3% (atomic fraction), adding excessive Nb will make the coercivity of the alloy drop rapidly and make Nd2Fe14B unstable The addition of gallium Ga can significantly increase the coercivity of the alloy and reduce the irreversible magnetic field. In the Nd-Fe-Co-B series alloy, as the content of Co increases, the Hcj of the alloy decreases, but when Ga is added Bottom, the coercivity increased. It is expected that it is possible to prepare Nd-Fe-B permanent magnet materials with high Curie point and high Hcj in alloys with Ga added The compound addition of gallium Ga and niobium Nb can significantly improve the temperature stability of the alloy. Dy Ga Ho La

How to Improve the Charging Efficiency of Wireless Charging and Ensure Its Safety ?

a. What is the Disadvantages of Wireless Charging and Why?1.     Easy to heat up 2.     Short sensing distance3.     Long charging time4.     Low charging efficiencyBecause the electromagnetic field interacts with the surrounding metal environment to generate electronic eddy currents and lose them in the form of heat energy, which wastes magnetic energy, weakens magnetic induction, shortens charging distance.                                 b. What is the Main Solution to Improve the Charging Efficiency of Wireless Charging and Ensure Its Safety and Why?The main solution is to attach magnetic shielding materials to the back of the wireless charger transmitter and receiver coils.Because It will provide a smooth magnetic path for the sympathetic electromagnetic field, which will increase the efficiency of wireless charging. And it will prevent the interaction between the sympathetic electromagnetic field and the surrounding metal environment from generating eddy currents, dissipating heat and wasting electrical energy, which will increase the sensing distance and save energy                                 c. What is the Requirements for the Magnetic Shielding Materials?1.     Excellent magnetic properties 2.     High permeability3.     Good flexibility, and will not be broken during bonding, otherwise it will cause magnetic leakage.4.     Little magnetic loss in an AC magnetic field                           

Some tips of wireless charging

Is wireless charging safe? It is very safe to contact the wireless charger closely. When your smart phone is actually in contact with the charging base, the signal will be concentrated to the receiving coil of the mobile phone, thus starting charging. Compared with the mobile phone connected to the mobile network, the radiation emitted by the entire wireless charging process is much smaller. Will the wireless charger get hot? During the charging process, all chargers will generate a certain amount of heat. Indoor chargers, charging bases and even portable power banks will lose a certain amount of energy in the form of heat. Wireless chargers are no exception. Is it safe to overcharge the smartphone? Most charging pads will use trickle mode to safely charge the mobile phone battery to ensure that the mobile phone battery is always fully charged, so it is safe to leave the mobile phone on the charging pad overnight and even longer. Trickle charging refers to: when the mobile phone is placed on the charging board, if the battery charge falls below 100%, a small amount of current will be provided to the battery to ensure that it is always fully charged. Electrical Surge Although your charging pad or charging base is connected to a wall outlet, the socket may be affected by lightning strikes and other electrical surges, but the wireless charger will not pass the increased voltage to your smartphone. Therefore, wireless charging is safer than using a power outlet to charge a smartphone. What if there is a foreign material on the wireless charger? Maybe keys or coins. These may cause the charging pad to continue to discharge, which will not only damage your device, but may also melt foreign material on the charging pad. Therefore, it is very important to find a charger equipped with a foreign object detection device. Once a foreign object is found, an alarm will sound-usually with an LED light, indicating that a foreign object other than a compatible device has touched the charger. This will help prevent charging hazards.

The magnetic materials in the wireless charging

Wireless charging has become popular in mobile phones, and they become standard devices. There are also a lot of products in the wearable space. In the future, wireless charging will be widely used in homes, offices, public places, transportation tools and transportation. There will also be widespread use of electric cars in the future. Application of wireless energy transmission (WPT) : smart phone, smart wear (small power) The structure of wireless charging It is similar to that of a transformer, which consists of a transmitter and a receiver, both of which are composed of coils and magnetic materials. There are different kinds of magnetic materials, such as ferrite, amorphous and nanocrystalline. The role of soft magnetic shielding material in wireless charging Magnetic shielding: provides a low impedance path for magnetic flux, reduces the magnetic field lines emitted to the outside, reduces the impact on the surrounding metal objects, and prevents eddy current and signal interference. Magnetic resistance reduction: improve coupling coefficient, improve magneto-electric conversion efficiency,  use fewer turns to achieve higher inductance coil, reduce coil resistance, reduce the efficiency reduction  caused by heat (more turns, higher resistance). Comparison of charging efficiency of nanocrystalline magnetic conducting tablets In order to simulate the real situation and conduct comparative test under the same conditions, the charging efficiency of nanocrystalline magnetizers with different thickness and ferrites with different permeability and thickness are compared. With the increase of the thickness, the charging efficiency is improving, but the nanocrystalline is not thicker, and it is basically saturated at 0.1mm. Therefore, when designing the wireless charging module, the nanocrystalline magnetic conducting plate does not need to be too thick, which will increase the material cost. The rule of ferrite is similar to that of nanocrystalline. The higher the permeability, the higher the charging efficiency, and the thicker the thickness, the higher the charging efficiency. However, at the same charging efficiency, the thickness of nanocrystalline magnetic sheet is only half of that of ferrite. Application cases Nanocrystalline applications for wireless charging began with S7, a material that does all the work, replacing a combination of amorphous and ferrite. It is generally believed that used in the NFC soft magnetic materials, ferrite is the best, and that nanocrystalline doesn't fit, because in high frequency, the wastage of the nanocrystalline outweigh the ferrite, but  research personnel made a breakthrough, the successful application of S7 proved nanocrystals can be used in the NFC, then the S8 / N8 / A7 / J5 / J7 many models such as products, to expand the application of nanocrystalline from WPC to NFC and MST.  Mobile phone wireless charging development trend:  1,Function: the WPC - WPC + NFC - WPC/Airfule + NFC 2,Wireless charging -- wireless charging + -- charging at will 3,Power: the 5 W - 7.5 W - 10 W - 15 W 4,Slow charge -- universal charge -- quick charge -- flash charge Application and popularization Low power: mobile phone, smart wear, etcMedium power: computer, kitchen appliances, etcHigh power: electric vehicles, roads and other infrastructureThe future, will be the wireless world, change life, change the world.

Permeability magnetic material in wireless charging

Wireless charging technology has been repeatedly mentioned in recent years. With the further popularization of this technology, the wireless charging function in public places has also developed, but what is the wireless charging technology? In 1890, physicist and electrical engineer Nikola Tesla had already done a wireless transmission experiment. The fundamentals of wireless charging Wireless charging is designed based on the principle of electromagnetic induction. The core of electromagnetic induction is to modify the transformer. The transformer is composed of a magnetic core and a coil, one is on the mobile phone, and another is on the power supply. When the two are combined, the magnetic force attracts each other to produce wireless power transmission. Internal structure of wireless charging Inside the transmitter has: 1. DC power input; 2. Frequency generating device; 3. Switching power; 4. Resonant combination of transmitting coil and capacitor; Outside the receiver has: 1. Received coil and capacitor resonance combination; 2. Rectifier; 3. Filter and voltage regulator; 4. DC power output; How wireless charging works The main types of magnetic barriers applied to wireless charging Hard magnetic material (represented by Ferrite)The Ferrite sheet sintered at high temperature has high magnetic permeability, and the material is hard and easy to crack. It is commonly used in the transmitter end of wireless charging. How does the magnetic material work The magnetic material plays an important role in wireless chargingThe addition of magnetic material will increase the magnetic flux of the coil, the closed magnetic field is safer, and it will not interfere with the mobile phone signal. The main working principle is that there is a coil at the sending and receiving ends. Electromagnetic signal, the receiving coil induces the electromagnetic signal of the transmitting end to generate current to charge the battery; attaching a magnetic material to the transmitting antenna can enhance the magnetic field strength of the coil, and at the same time has a high magnetic convergence effect; placing a magnetic sheet at the receiving antenna Prevent the attenuation and interference of metal conductors on the magnetic field, play the role of metal isolation, prevent waste of energy, and improve charging efficiency.

Application of Nanocrystalline Soft Magnetic Materials in Wireless Charging

Application of Nanocrystalline Soft Magnetic Materials in Wireless Charging 1. What is a nanocrystalline? First of all, we have to understand what is amorphous? During the preparation of the metal, if it is cooled with an ultra-fast cooling rate during its solidification process, the atoms are in a disorderly state at this time, and they will be instantly frozen before they can be rearranged. The structure formed at this time is Amorphous. Nanocrystalline is based on the amorphous state, through a special heat treatment, let it form crystal nuclei and grow. However, it is necessary to control the size of the crystal grains at the nanometer level, and do not form complete crystals. The structure formed at this time is nanocrystalline. 2. Advantages of nanocrystalline Compared with cobalt-based amorphous and ferrite, nanocrystalline has a high saturation magnetic inductance and can reduce the volume of magnetic devices. High magnetic permeability, small loss, and small coercive force can reduce the loss of magnetic devices. Therefore, nanocrystalline are the best soft magnetic materials in high-frequency power electronics applications. 3. Characteristics of nanocrystalline The frequency of the current wireless charging "Qi standard" is between 100-200k. At this frequency, the magnetic permeability of the nanocrystalline is very close to that of the cobalt-based amorphous, which is significantly higher than that of the iron-based amorphous and ferrite . The loss is just the opposite, significantly lower than iron-based amorphous and ferrite. Nanocrystalline also have advantages in temperature applications. Not only are nanocrystalline wider in application temperature than cobalt-based amorphous and ferrite, but in the range of -40℃-120℃, the stability of nanocrystalline is also significantly better than ferrite. Nanocrystalline also have obvious advantages in the design of magnetic materials. Nanocrystalline can be oriented to control permeability and anti-saturation magnetic fields. The magnetic permeability of nanocrystalline can be adjusted freely within 1000-30000. The design of the magnetic material requires that the magnetic saturation should not be reached under a specific working current. Once the magnetic saturation is reached, it will stop working. The nanocrystalline adjustable anti-saturation magnetic field can reach 30~350A/m, making the application range of wireless charging more width. 4. Application of nanocrystalline soft magnetic materials in wireless charging Wireless charging has become popular in mobile phones, and there are many products in the wearable field. In the future, wireless charging will be popularized in homes, offices, public places, travel tools, and transportation. Wireless power transmission (WPT): The structure of wireless charging for smart phones and smart wearables (small power) is similar to a transformer. It consists of a transmitter and a receiver. The transmitter and the receiver are both made of coils and magnetic materials. The magnetic materials are different. The choices are ferrite, amorphous, nanocrystalline, etc. 5. The role of soft magnetic shielding materials in wireless charging Magnetic shielding: Provide a low-impedance path for the magnetic flux, reduce the magnetic field lines radiating outward, reduce the impact on the surrounding metal objects, and prevent eddy currents and signal interference. Permeability reduction: improve the coupling coefficient, improve the magnetoelectric conversion efficiency, use fewer turns to achieve a higher inductance coil, reduce the coil resistance, and reduce the efficiency reduction caused by heating (the more turns, the higher the resistance) . 6. Comparison of charging efficiency of nanocrystalline magnetic permeable sheets Simulating real scenes, conducting comparative tests under the same conditions, using different thickness nanocrystalline magnetic sheets and ferrite with different permeability and thickness to compare the charging efficiency. As the thickness increases, the charging efficiency continues to increase, but the nanocrystalline is not as thick as possible, basically saturated by 0.1mm, therefore, when designing a wireless charging module, the nanocrystalline magnetic permeable sheet does not need to be too thick, it will Increase material cost. The law of ferrite is similar to that of nanocrystals. The higher the magnetic permeability, the higher the charging efficiency, the thicker the thickness, and the higher the charging efficiency. However, under the same charging efficiency, the thickness of the nanocrystalline magnetic sheet is only the ferrite. half.