Controlled oxidation and reduction cycles are thermal processes in which the amount of oxygen in the atmosphere is precisely regulated to achieve specific chemical changes in a material. Oxidation cycles introduce and control oxygen levels to promote reactions that form oxides or alter surface chemistry, while reduction cycles limit or remove oxygen to reverse oxidation or produce reduced compounds. These cycles are used in applications such as metallurgy, catalyst preparation, material synthesis, and surface treatment, where consistent chemical transformation is essential for product performance.