Aluminum carbide is a salt-like compound characterized by high melting point and hardness. It is also an important abrasive material for a variety of applications. In addition, it has high wear resistance and electrical conductivity.
The chemical formula of aluminum carbide is Al4C3. When aluminum atoms are oxidized by CO2, they form Al4C3 and Al2O3. These particles are carried to the surface by reactive gas.
Aluminum carbide is stable up to 1400 degC. In aqueous solution, its thermal stability depends on the acidity of the solution. At 700 degC, its Gibbs energy is 1893.4 kJ.
Aluminum carbide is formed in a furnace. Carbon anodes are used in the production process. During the synthesis, the hydrogen atom of methane is displaced by metal atoms. An ionic bond, also known as a molecular bond, forms between the atoms.
This chemical bond is a permanent attraction between the ions. To promote the formation of carbide, a variety of chemical reactions take place. One of the earliest synthesis processes is direct metal carbonization. However, its disadvantages are high synthesis temperature, large particle size, and long reaction time.
Another way of synthesizing aluminum carbide is by high-energy ball milling. Its main advantages are in-situ synthesis of a small amount of Al4C3. But its major shortcomings are the high energy consumption and the uneven powder particles in the ball mill itself.
Using the ball milling technique, aluminum grain size was reduced to 30 nm. EDS analysis showed that multiple Al-C peaks were detected in the particles.