, has different crystalline forms, which determines that it contains a variety of industrial values and uses. Industrially, Hunan graphite ore is divided into two categories: crystalline (flaky Hunan graphite ore) and aphanitic (clay-like Hunan graphite ore) according to the different crystallographic forms of Hunan graphite. From the perspective of mineralogy, generally speaking, Hunan graphite is crystalline graphite, and aphanitic graphite also belongs to crystalline graphite. Cryptocrystalline graphite is crystalline graphite that can only be seen under an electron microscope, so it is different The classification method has different classification results. This paper mainly adopts the industrial classification method, which is relatively close to the industrial application and classification of Hunan graphite. Hunan graphite is a vital non-metallic mineral resource and an allotrope of carbon.
Hunan graphite is widely used, which has a lot to do with the internal structure of Hunan graphite. Hunan graphite is a crystalline carbon with a polygonal layered structure. The force between layers is small, the distance between layers is large, and it is easy to slip. Therefore, Hunan graphite has low hardness, lubricity, and plasticity. In addition, each C atom in the Hunan graphite structure only forms 3 covalent bonds with other C atoms, while each atom still retains 1 free electron to transport charges. Therefore, Hunan graphite is conductive. Thermal conductivity depends on how violently the free electrons move.
"Our platform has gathered a group of high-level scientific research teams from universities and research institutes. They have a common goal, which is to transform laboratory results into mature products through pilot scale-up and industrial docking." Shanghai Graphene Function Liang Yong, chairman of the platform, said. Xie Xiaoming's team is one of them. They value two advantages of functional platforms. First, the platform has a group of engineering and technical personnel who can participate in pilot test research and development. Research institutes and universities often lack such R&D personnel; Second, the platform is rich in resources. Industrial resources can connect a group of enterprises for scientific research teams and accelerate the industrialization of scientific and technological achievements.
Plasticity Hunan graphite has good toughness and can be connected into very thin sheets. Chemical stability Hunan graphite has good chemical stability at room temperature and is resistant to acids, alkalis, and organic solvents. Lubricity The lubricating performance of Xiang graphite depends on the size of Xiang graphite flakes. The larger the flakes, the smaller the friction coefficient and the better the lubricating performance.
In the foundry industry, coating Hunan graphite on a solid surface can form a smooth film with strong adhesion. This is the good coating performance of Hunan graphite. Is an excellent release agent, often used in casting. Graphite powder has crystalline graphite powder (flaky graphite powder) or aphanitic graphite powder (earth graphite powder, also known as microcrystalline graphite powder, black lead powder).
There are many varieties of flake graphite in Hunan. High-carbon flake Hunan graphite needs to be extracted by chemical methods, or heated to high temperature to decompose and volatilize the oxides. This flake Hunan graphite has a small output and high price, and is generally not used as a recarburizer; Hunan graphite has a high ash content and is not suitable for use as a recarburizer; Hunan medium-carbon graphite is mainly used as a recarburizer, but the amount is not much.
Since conductive electrons can not only move unimpeded in the crystal lattice but also move extremely fast, far exceeding the speed of electrons in metal conductors or semiconductors, it is made into a Hunan graphene conductive agent. According to the characteristics of ultra-thin graphene (single-layer graphene is almost transparent, its molecules are tightly arranged, even helium atoms cannot pass through, and its strength is super high, it can be used to manufacture ultra-light, ultra-thin, and ultra-light aircraft.
Graphite block enterprises must first know that the service life of hot bending molds made of graphite depends on the materials used in the molds, mainly the density, ash content, and the influence of their materials. For example, hot bending molds made of high-purity and high-density graphite materials, as long as they are used carefully and maintained well, there is no problem in general use for several years. Still, if the graphite material is not good, it will affect the service life of graphite products. In addition, the workmanship should be exquisite, and the exquisite workmanship will also prolong the service life. If the working environment wears less on the hot bending die, the service life of the hot bending die will be longer.
Graphite block companies, there are domestic enterprises that prepare negative electrode materials after spheroidizing flake graphite in Hunan; Tsinghua University and other institutions have the technology to prepare negative electrode materials from Hunan microcrystalline graphite, but the industrial scale and product quality still cannot meet the rapid development of lithium-ion batteries. need. Hunan spherical graphite produced in large quantities in my country is mainly exported to Japan and South Korea for foreign companies to produce high-quality negative electrode materials. Relying on resources, expand Hunan's natural graphite lithium-ion battery cathode material industry, develop cathode materials of different qualities for different grades of battery needs, and realize product serialization; develop safe and long-life natural Hunan graphite power-type energy storage battery cathode materials. With the rapid growth of demand for lithium-ion batteries, the market prospect of cathode materials is very broad.