Fri, 13 Jul 2018 02:02:23 +0000
vacuum heat treatment process key points
What is the vacuum heat treatment process? Vacuum heat treatment is the combination of vacuum technology and heat treatment technology of a new type of heat treatment technology, vacuum heat treatment of vacuum environment is a under an atmospheric pressure of the atmosphere environment, including low vacuum, moderate vacuum, high vacuum and high vacuum, etc., vacuum heat treatment process in fact is also controlled atmosphere heat treatment. Vacuum heat treatment mainly refers to the process of vacuum heat treatment, which is carried out partially or completely in a vacuum state. Compared with conventional heat treatment, vacuum heat treatment at work and at the same time, also can realize no decarburization, oxidation and carburizing, can be removed by processing scales on the surface of the workpiece, and also have the function of the skim to gas, can make the surface of the workpiece more shining purification.
So for such vacuum heat treatment, what are the technical points of its process? Now let’s understand the key points of vacuum heat treatment.
1. Vacuum high-pressure air quenching technology
At present, the vacuum high-pressure gas cooling quenching technology is developing rapidly, there are already high negative pressure gas cooling flow rate, pressure air cooled, the high pressure gas cooling and ultrahigh pressure gas cooling and so on new technology, not only greatly improve the ability of vacuum cooling quenching, and after quenching, the workpiece surface brightness is very good also, the deformation is small, has advantages of no pollution, energy saving and high efficiency and so on.
The vacuum high-pressure gas cooling quenching technology is mainly used for stainless steel and special alloy limitation and solid solution, vacuum sintering, materials, quenching and tempering, ion carburizing and carbonitriding, and brazing after quenching and cooling etc.
2. Vacuum carburizing technology
Vacuum carburizing vacuum furnace was mainly used for steel mechanical parts such as the overall heating, filling the small amount of gas, under the conditions of low voltage reactive nitrogen atoms into and spreading in steel and a technology of hardening, vacuum carburizing carbon altogether permeability, also known as vacuum exhaust type nitrogen is its main characteristic is through the vacuum technology, make the metal surface purification and activation. In the heating, insulation and cooling of the heat treatment process, some not pure trace gases expelled, which contain active material is fed into the pure compound gases, let the workpiece surface phase structure adjustment and efficiency.
3. Vacuum cleaning and drying technology
At present, some heat treatment still cannot be separated from the process of cleaning and drying, especially the heat treatment that requires oil cooling. The task of cleaning and drying is quite complex and difficult. In the international use of the best effect of the cleaning agent should be halogen – line cleaning agent. And in these cleaning agents, trichloroethane and freon because of damage of atmospheric ozone layer, have been banned, and other halogen material is limited because of the will do harm to environment and human and animal use. Therefore, it is necessary to study the alternative cleaning and drying technology.