Three stages of graphite formation

The answers to the three stages of graphite formation are as follows:

The first stage: liquid-phase sub-* * crystallization stage, in which primary graphite (cast iron with * * * crystals) is crystallized by cast iron liquid, and * * * crystal graphite is formed through * * * crystallization reaction.

The second stage: the stage between * * * crystallization transformation and * * * folding transformation.

The third stage: * * precipitation transformation stage, in which graphite is precipitated by * * * precipitation reaction.

Extended data:

The meaning of graphite:

Graphite is an allotrope of carbon, which is a gray-black opaque solid with stable chemical properties, corrosion resistance and difficult to react with chemicals such as acid and alkali. Natural graphite comes from graphite deposits, and can also be made from petroleum coke and pitch coke through a series of processes.

Graphite burns in oxygen to produce carbon dioxide, which can be oxidized by strong oxidants such as concentrated nitric acid and potassium permanganate. Graphite can be used as antiwear agent and lubricant, high purity graphite can be used as neutron moderator in atomic reactors, and can also be used to manufacture crucibles, electrodes and brushes.

The role of graphite:

1. Energy storage: Graphite is an ideal electrode material, which is often used to store energy in lithium-ion batteries and supercapacitors. It has high capacitance, high conductivity and good cycle stability.

2. Electronic products: Graphite is used as a conductive material in electronic products, such as the circuit connection points of batteries, mobile phones and computers. It has excellent electrical conductivity and thermal stability.

3. High temperature lubricant: Graphite is often used as a high temperature lubricant due to the sliding between graphite layers. Reduce friction and wear under high temperature and high friction and provide effective protection.

4. Paper and pencil: Graphite is the main component of pencil lead, so you can write directly on paper. Graphite will leave black marks on the paper, because its layered structure will slide on the paper and release black pigments.

5. High-temperature materials: Because of its high thermal stability and thermal conductivity, graphite is widely used in high-temperature environments, such as nuclear power plants, aerospace and other fields.

6. Chemical industry: Graphite plays an important role in the chemical industry, such as manufacturing reactors, heat exchangers, valves and pipelines, because of its corrosion resistance and high temperature stability.

In a word, graphite is widely used in energy storage, electronic products, lubricants, writing tools and high temperature applications, and plays an important role in many fields.