Application of Ceramic Parts in New Energy Vehicles

With the continuous development of the automobile industry and people's increasing requirements for automobile environmental protection, energy saving, safety and comfort, automobile materials are also constantly changing. Especially under the wave of electrification, the system design of automobiles has undergone earth-shaking changes, and advanced ceramic materials are slowly emerging in the application of new energy automobile parts.

Ceramic materials in new energy vehicles Ceramic substrates
In electric vehicles, high-power packaging devices play a decisive role in regulating vehicle speed and storing-converting AC and DC. High-frequency thermal cycles put forward strict requirements on the heat dissipation of electronic packaging. At the same time, the complexity and diversity of the working environment require packaging materials to have good thermal shock resistance and high strength to play a supporting role.

The most widely used ceramic substrates are: Al2O3, BeO, SiC, Si3N4, AlN, etc. Among them, silicon nitride is recognized at home and abroad as the best ceramic substrate material with high thermal conductivity, high reliability and other comprehensive properties. But overall, from the perspective of thermal conductivity, wear resistance, mechanical properties and other characteristics, Si3N4 and AlN ceramic substrates have become substrate materials worthy of attention in the future.

Ceramic relay
Electrical control technology is an important indicator of the development level of new energy and energy-saving electric vehicles. High-voltage DC ceramic relays are the core components of the electronic control system. In a high-voltage DC vacuum relay, in a vacuum cavity sealed by metal and ceramic, the ceramic insulator is slidably connected between the moving contact assembly and the push rod, so that the moving contact and the static contact are in good electrical insulation from the magnetic circuit system composed of the relay's magnetic yoke iron plate, iron core and other parts in any state of conduction or disconnection, thereby ensuring the relay's arc-breaking ability when switching DC high-voltage loads. Arcs are the main cause of automobile spontaneous combustion. Only relay products that use "arc-free" connection and disconnection can fundamentally solve the problem of "spontaneous combustion".

Ceramic fuses
Automotive fuses are divided into low-voltage and high-voltage parts. High-voltage protection is mainly suitable for new energy vehicles. The application voltage is generally 60VDC-1500VDC. It is mainly power fuses (new energy vehicle high-voltage fuses) to protect the main circuit and auxiliary circuit. As the new energy vehicle market enters the high-voltage platformization, the safety requirements of high-voltage fields such as fast charging, motors, and power devices cannot be ignored. The fast breaking ability of fuses in stability and overcurrent response will maintain a high-speed increase in demand under the rapid growth of new energy vehicles.

MLCC for automobiles
Compared with traditional vehicles, the level of electrification of electric vehicles has been greatly improved. From the newly added electronic control and battery management system, from the audio and video entertainment system to the ADAS system to the fully automatic driving system, etc., the improvement of the level of automotive electronics has greatly promoted the growth of automotive MLCC.
The demand for MLCC varies with the degree of electrification of models. One pure electric vehicle requires up to 18,000 MLCCs. With the continuous deepening of the trend of the new four modernizations of automobiles, the demand for automotive-grade MLCC is growing.

Ceramic bearings
Under the wave of electrification, new energy vehicles have put forward more new requirements for automotive bearings. First, compared with traditional bearings, motor bearings have a high speed and require lower density and relatively more wear-resistant materials; at the same time, due to the changes in the surrounding electromagnetic field caused by the alternating current of the motor, better insulation is required to reduce the electrical corrosion caused by bearing discharge; third, the surface of the bearing ball is required to be smoother and less worn. Among ceramic materials, silicon nitride ceramic bearings are considered to be the best materials for manufacturing automotive bearings because of their advantages of light weight, high hardness, high strength, low friction, high heat resistance, excellent electrical insulation and long life.

Carbon ceramic brake disc
Carbon ceramic (C/C-SiC) composite material is a new type of brake pad material developed on the basis of carbon/carbon composite material. The material is composed of quasi-three-dimensional carbon fiber integral needle felt as the skeleton reinforcement and deposited carbon, SiC and residual silicon as the matrix. The material combines the physical properties of carbon fiber and polycrystalline silicon carbide, and has the characteristics of high temperature stability, high thermal conductivity and high specific heat.

Under the trend of electrification, intelligence and high-end in the new energy vehicle industry, the carbon ceramic brake system can significantly improve the vehicle response speed and shorten the braking distance. It is expected to become the best actuator for wire control braking and can be said to be the key weight reduction component of electric vehicles in the future.

Ceramic diaphragm
With the increase of lithium battery energy density, the requirements for diaphragms will also increase. Ceramic materials have become the development direction of future power battery diaphragms with their low thermal conductivity, high safety and good affinity with electrolytes. Commonly used ceramic materials include α-alumina, boehmite, etc.

Ceramic body, chassis and other structural parts
The new ceramic aluminum material has the characteristics of high strength and light weight, heat resistance and fatigue resistance, shock absorption and low expansion, easy processing and easy plasticity. This material combines the advantages of ceramic particles and aluminum alloys, breaks through the performance limitations of a single material, and has the superior properties of light weight, high stiffness, high strength, high fatigue resistance, and high temperature resistance. It is applied to various parts of automobiles, such as body structural parts, automobile chassis parts, etc., to achieve the goals of reducing automobile weight, reducing costs, and improving fatigue life, while also reducing costs.

Optical components
Transparent ceramics refer to polycrystalline materials with certain light transmittance prepared by ceramic technology, also known as optical ceramics. Compared with glass or resin optical materials, transparent ceramics not only have similar light transmittance quality as optical glass, but are also stronger, harder, more corrosion-resistant, and more resistant to high temperatures. They can be used in extremely harsh working conditions, and the refractive index can be changed. At present, some manufacturers in the industry have been trying to use transparent ceramic materials as vehicle-mounted camera lenses, laser radar window materials, laser optical devices, etc.

Advanced ceramic materials are composed of ionic bonds or covalent bonds, so they have excellent properties such as high strength, high hardness, high temperature resistance, wear resistance, corrosion resistance, and good biocompatibility. They are high-quality materials for new energy vehicle parts.