The carbonization process used to create carbon fiber is called pyrolysis, which uses nitrogen gas and heat as a catalyst to increase the vibrational energy of the atoms. Pyrolysis breaks the bonds between carbon atoms and nitrogen atoms, as well as the bonds between carbon atoms and oxygen atoms. As a result, the polymer structures formed during cross-link stabilization are converted into hexagonal carbon structures. Non-carbon atoms such as oxygen and nitrogen are removed as gases through the atmosphere. The final carbon content is more than 90% after carbonization, and the temperature range of carbonization is 900 to 1600 °C in an inert atmosphere. Heat treatment, optimal tension, completion of reactions, and maintenance of the molecular orientation of the precursor fiber are vital variables to produce a more perfectly aligned crystalline structure and improve the tensile strength of the fiber