Pressure range of vacuum furnace

The partial pressure range of a vacuum furnace refers to the partial pressure levels of various residual gases within the total pressure after vacuuming. Since a vacuum environment is not completely gas-free but composed of various gases such as nitrogen, oxygen, hydrogen, and water vapor, the partial pressure range directly affects the degree of oxidation and material reaction during the process.

In conventional industrial vacuum heat treatment processes, the total vacuum level typically reaches 10⁻¹ Pa to 10⁻³ Pa. At this level, the partial pressures of various residual gases are correspondingly lower, with the partial pressures of water vapor and oxygen usually controlled at even lower levels to reduce the risks of oxidation, decarburization, and contamination. This stage is suitable for most metal annealing, brazing, and quenching processes.

In demanding processes or under high vacuum conditions (such as 10⁻³ Pa to 10⁻⁵ Pa), the partial pressures of residual gases are further reduced, especially the partial pressures of oxygen and water vapor, which are controlled at extremely low levels, thereby significantly reducing surface reactions and the influence of impurities. When necessary, the partial pressure can be adjusted by filling with an inert gas (such as argon) to meet the process requirements of special material processing or precision heat treatment.