The primary processes of QPQ treatment include preparation, cleaning, preheating, salt bath quenching, tempering, and post-treatment. During the preparation stage, metal surfaces must be cleaned and pre-treated to remove oil, dirt, and oxides to ensure treatment quality. Preheating is to fully heat the metal surface to promote the uniformity of quenching and tempering. Salt bath quenching involves placing the metal in a high-temperature salt bath, rapidly heating and holding it for a certain period, then rapidly cooling it to form a hardened layer on the metal surface. Tempering is the process of reheating the hardened metal to stabilize its structure and properties. Post-treatment then follows, which includes cleaning, drying, and coating, completing the entire process.

The advantages of QPQ processing lie in its environmental friendliness and energy efficiency. Compared to traditional heat treatment techniques, QPQ processing has lower temperatures and shorter times, significantly improving production efficiency and reducing energy consumption. Additionally, the salt bath medium used in the QPQ process boasts high chemical stability and low corrosiveness, making it environmentally friendly. The treated metal surfaces also exhibit high quality, with excellent wear resistance, corrosion resistance, and fatigue resistance. Therefore, QPQ processing technology holds broad application prospects in the field of metal surface treatment.