The application of various advanced materials
The material industry is the cornerstone of modern industry, and in the intelligent automobile industry, the application of various advanced materials is also the basis of supporting the entire industry. Here, let's take a look at the materials that occupy an increasingly important position in the process of automotive intelligence - ceramic materials.
1. Classification and performance advantages of ceramic materials
Ceramic materials are a large category, which refers to a class of inorganic non-metallic materials made of natural or synthetic compounds by forming and sintering at high temperature. It has the advantages of high melting point, high hardness, high wear resistance and oxidation resistance.The application in modern industry is mainly based on high purity, ultra-fine synthetic inorganic compounds as raw materials, using precision control process sintering and made of new ceramic materials. Its components are mainly oxides, nitrides, borides and carbides. At present, ceramic materials commonly used in the automotive field include silicon nitride (Si3N4), silicon carbide (SiC), zirconium dioxide (ZrO2), beryllium oxide (BeO), alumina (A12O3), etc., for structural components and functional components on the car, so it is also divided into structural ceramics and functional ceramics.
To understand a material, let's first look at its advantages and disadvantages in terms of performance:
1. Performance advantage
The new ceramic material is an atomic crystal material, its structure is similar to diamond, which is what we often say diamond, so its physical properties are also very similar in some aspects, such as high hardness. The following is a summary of the performance advantages of ceramic materials: High hardness, dimensional precision: Ceramic materials generally have extremely high hardness/stiffness, which directly translates into excellent wear resistance, meaning that many technical ceramics are able to maintain their precise, high-tolerance finish longer than any other material. Compressive strength: The new ceramics have very high strength, but only when compressed. For example, many precision ceramic materials can withstand extremely high loads of 1000 to 4000 MPa. Titanium, on the other hand, is considered to be a very strong metal with a compressive strength of only 1000 MPa. Low density/Lightweight: Another common feature of precision ceramics is their low density, from 2 to 6 g/cm³. This is lighter than stainless steel (8 g/cc). High dielectric strength (insulation) : They are particularly useful in high temperature applications where the mechanical and thermal properties of other materials tend to degrade. Some ceramics have low electrical loss and
high dielectric constant; These are commonly used in electronic applications such as capacitors and resonators. In addition, combining insulators with structural components has resulted in many product innovations. High temperature resistance: Ceramic material is a kind of ultra-high temperature material, its melting point temperature is mostly more
than 1500℃. There are already some examples in high temperature applications such as engines, turbines and bearings. Thermal conductivity and insulation properties: The thermal properties of different types of ceramic materials vary greatly. There are some ceramics (aluminum nitride) that have high thermal conductivity and are often used as heat sinks or exchangers in many electrical applications. Other ceramics have much lower thermal conductivity, making them suitable for a wide range of applications. Chemical inertness and corrosion resistance: The chemical stability
of ceramic materials is very good, and the chemical solubility is low, so it has high corrosion resistance. Metals and polymers do not offer the same inertiability or corrosion resistance, which makes ceramics an attractive choice in many commercial and industrial applications, especially where wear resistance is also required.
2. Disadvantages of ceramic materials
While having the above advantages, ceramic materials inevitably have some difficulties; Poor shear and tensile strength, high brittleness, poor ductility; It is difficult to design and process. Thanks to the excellent electrical properties, mechanical properties and heat resistance of ceramics, they have a wider range of applications in the harsh requirements of the vehicle gauge level. For example, it is used as various electronic components such as resistors, capacitors and inductors; Because of its excellent thermal conductivity, it can be used as ceramic substrate of various power devices and sensor chips. In addition, ceramics can also be used in traditional fuel engines, new energy lithium batteries, brake pads, ceramic valve plates and so on.
