Difference Natural Graphite&Artificial Graphite

Difference Natural Graphite&Artificial Graphite

Natural graphite is rich in carbon organic matter under the long-term action of high temperature and high pressure geological environment, is the gift of nature. The process characteristics of natural graphite are mainly determined by its crystalline morphology. Graphite minerals with different crystalline morphology have different industrial values and uses.

There are more kinds of natural graphite, according to different crystalline morphology, natural graphite is divided into three types of dense crystalline graphite, flake graphite and cryptocrystalline graphite.

Artificial graphite is analogous to polycrystals in crystallography. There are many kinds of artificial graphite and different production techniques. In a broad sense, all the graphite materials obtained by organic carbonization and graphitization high temperature treatment can be collectively referred to as artificial graphite, such as carbon (graphite) fiber, pyrolytic carbon (graphite), graphite foam, etc..

01 Crystal Structure

The crystal development of natural graphite is more perfect, the graphitization degree of natural flake graphite is usually above 98%, while the graphitization degree of natural microcrystalline graphite is usually below 93%.

The degree of crystal development of artificial graphite depends on raw materials and heat treatment temperature. Generally speaking, the higher the heat treatment temperature, the higher the graphitization degree. The current industrial production of artificial graphite, its graphitization degree is usually less than 90%.

02 Organizational Structure

Natural flake graphite is a single crystal with a relatively simple structure, with only crystallographic defects (point defects, dislocations, stacking faults, etc.), and macroscopically showing anisotropic structural characteristics. The grains of natural microcrystalline graphite are small, the grains are disorderly arranged, and there are pores after the impurities are removed, showing the isotropic structural characteristics on the macroscopic level.

Artificial graphite can be regarded as a kind of multiphase material, including the graphite phase transformed by carbonaceous particles such as petroleum coke or pitch coke, the graphite phase transformed by coal pitch binder coated around the particles, and the pores formed by particle accumulation or coal pitch binder after heat treatment.

03 Physical Form

Natural graphite usually exists in powder form and can be used alone, but is usually used in combination with other materials.
The shape of artificial graphite is more, both powder, fiber and block, and the narrow sense of artificial graphite is usually block, when used to process into a certain shape.

04 Physical and Chemical Properties

Natural graphite and artificial graphite have commonness, also exist the difference on the performance. For example, natural graphite and artificial graphite are good conductors of heat and electricity, but for the same purity and particle size of graphite powder, natural flake graphite heat transfer performance and conductivity is the best, natural microcrystalline stone ink second, artificial graphite lowest.

Graphite has good lubricity and certain plasticity, natural flake graphite crystal development is more perfect, friction coefficient is small, the best lubricity, the highest plasticity, and dense crystalline graphite and cryptocrystalline graphite, artificial graphite is poor.

05 Application Field

Graphite has many excellent properties, so it is widely used in metallurgy, machinery, electrical, chemical, textile, national defense and other industrial sectors. The application fields of natural graphite and artificial graphite have overlapping parts, but also have different places.

In metallurgical industry, natural flake graphite can be used to produce refractory materials such as magnesium carbon brick and aluminum carbon brick due to its good oxidation resistance.

Artificial graphite can be used as the electrode for steelmaking, but the electrode made of natural graphite is difficult to be used in the harsh conditions of steelmaking electric furnace

In the mechanical industry, graphite materials are usually used as wear-resisting and lubricating materials. Natural flake graphite has good lubricity and is often used as an additive in lubricating oil.

Natural graphite and polymer resin composites can also be used in the above fields, but wear resistance is not as good as artificial graphite.

Artificial graphite has the characteristics of corrosion resistance, good thermal conductivity, low permeability, and is widely used in the chemical industry to make heat exchangers, reaction tanks, absorption towers, filters and other equipment.

Natural graphite and polymer resin composites can also be used in the above fields, but the thermal conductivity, corrosion resistance is not as good as artificial graphite.