Friction characteristics of carbon graphite at high temperature

When the carbon graphite material and the metal are rubbed at high temperature, the oriented crystal film formed on the two friction surfaces is composed of carbon-graphite particles peeled off from the carbon-graphite material. Carbon graphite is now widely used as a wear-resistant material to reduce the friction of the material, improve the wear resistance and prolong the service life. The carbon graphite in the Franli factory has a special crystal structure and chemical bond, which makes the carbon graphite have some special process properties at high temperature.

On the one hand, metal nanoparticles are supported on carbon graphite as a carrier. Metal nanoparticles, especially commodity nanoparticles, have great volatility and catalytic activity, and are widely used in catalysts, sensors, and other fields. However, as the size decreases, the increase of its surface energy will lead to aggregation between particles, and the carbon graphite as a template to support metal nanoparticles can play a role in physical isolation, avoid particle aggregation, and enhance its activity. In addition, carbon graphite can be coupled with metal nanoparticles and controllably assembled into a three-dimensional structure to complete the multi-functional use of the material.

Carbon graphite at high temperature

1.Due to the unsaturated bonds generated when the carbon-graphite crystal is peeled off, the crystal film and the friction surface generally have sufficient link strength. After a period of high temperature, a carbon-graphite film is formed on the surface of the metal and carbon-graphite. Its thickness and degree of orientation Both reach a certain value, the carbon graphite wears faster at the beginning, and then drops to a constant value.

2.The carbon graphite friction surface has the best orientation, the smallest crystal film thickness, and the largest adhesion force. This friction surface can ensure the smallest wear rate and friction coefficient at the end of the friction.

3.Carbon graphite materials have high thermal conductivity and excellent heat resistance, so the sliding speed has little effect on the friction coefficient and wear rate. It helps to quickly dissipate heat from the friction surface, so that the temperature inside the material and the friction surface can be balanced under a fixed temperature condition. The friction surface of the carbon-graphite film has been formed. In a certain pressure range, the wear rate remains constant. If the pressure continues to increase, the oriented film will be severely damaged, and the wear rate and friction coefficient will also increase accordingly.

Advantages of carbon graphite at high temperature

High-purity carbon graphite has the advantages of small resistivity, high temperature resistance, corrosion resistance, soothing reactivity, good thermal shock resistance, small thermal conductivity and thermal expansion coefficient, self-lubricating, and easy and accurate machining.

(1) High temperature resistance: the melting point of carbon graphite is 3850 ± 50 °C, and the boiling point is 4250 °C. Even if it is burned by a very high temperature arc, the weight loss is very small, and the thermal expansion coefficient is also very small. The strength of carbon graphite increases with the increase of temperature, and at 2000 ℃, the strength of carbon graphite doubles.

(2) Electrical and thermal conductivity: The electrical conductivity of carbon graphite is one hundred times higher than that of ordinary non-metallic minerals. The thermal conductivity exceeds that of metal materials such as steel, iron, and lead. The thermal conductivity decreases with increasing temperature, and even at higher temperatures, carbon graphite becomes a thermal insulator. Carbon graphite can conduct electricity because each carbon atom in carbon graphite forms only 3 covalent bonds with other carbon atoms, and each carbon atom still retains 1 free electron to transmit charges.

The Franli factory has accumulated rich experience in the friction coefficient of carbon graphite and surface porous materials in the high temperature environment through the practical experiments on the friction coefficient of carbon graphite and surface porous materials for many years. Carbon graphite that maintains the smallest coefficient of friction and maximizes thermal conductivity. It has super high temperature resistance, thermal conductivity and lubricity. The Franli factory is dedicated to the research of carbon graphite, mainly producing high-quality carbon graphite, as well as a complete set of flow equipment and precision instruments. There are different types of carbon graphite according to different customers and different uses.