What is a vacuum atmosphere furnace?

Vacuum atmosphere furnace is a new type of heat treatment equipment that combines vacuum technology with heat treatment technology, also known as oxygen free annealing furnace, vacuum atmosphere sintering furnace, etc. It can undergo heat treatment in an atmosphere environment below one atmosphere, including low vacuum, medium vacuum, high vacuum, and ultra-high vacuum states. This technology is actually a type of atmosphere controlled heat treatment. The following is a detailed introduction about vacuum atmosphere furnaces:
1. Working principle
The working principle of a vacuum atmosphere furnace mainly involves three processes: heating, vacuum extraction, and atmosphere control:
Heating process: The heating system of a vacuum atmosphere furnace usually uses electric heating elements or gas burners to transfer heat to the materials in the furnace through radiation and convection. During the heating process, the temperature distribution and heating rate inside the furnace can be precisely controlled as needed.
Vacuum extraction process: The vacuum atmosphere furnace is equipped with a vacuum system, mainly used to extract gas from the furnace and create a high vacuum environment. The core components of a vacuum system include a vacuum pump and vacuum measuring instruments, which work together to maintain a vacuum state in the furnace.
Atmosphere control process: In a vacuum atmosphere furnace, the atmosphere control system is used to control the composition and flow rate of gas in the furnace. By introducing specific gases (such as inert gases, reducing gases, or oxidizing gases) into the furnace, precise atmosphere control can be achieved to meet experimental or production needs.
2. Main advantages
The main advantages of a vacuum atmosphere furnace include:
Reducing harmful effects: It reduces the adverse effects of harmful components (water, oxygen, nitrogen) in the atmosphere on the product. For example, as long as the vacuum degree reaches 133Pa, it is equivalent to a dew point with a water content of -40 ℃, and obtaining such a vacuum degree is not difficult.
Wide application range: For materials that are not suitable for using reducing or inert gases as a protective atmosphere (such as sintering of active metals), or materials that are prone to decarburization and carburization, vacuum sintering can be used.
Improving material properties: Vacuum can improve the wettability of liquid to solid phases, which is beneficial for shrinkage and improving the microstructure of alloys; At the same time, it helps to eliminate impurities such as silicon, aluminum, magnesium, calcium, or their oxides, playing a role in purifying materials.
Promoting sintering: Vacuum is beneficial for removing adsorbed gases, residual gases in pores, and reaction gas products, and has a significant effect on promoting shrinkage in the later stage of sintering.
Lowering sintering temperature: The vacuum sintering temperature is lower than that of gas shielded sintering. For example, when sintering hard alloys, the sintering temperature can be reduced by 100-150 ℃, which is beneficial for reducing energy consumption and preventing grain growth.
3. Application field
Vacuum atmosphere furnaces have a wide range of applications in various fields, including:
Materials science: used to study the physical and chemical properties of materials under extreme conditions.
New material research and development: plays an important role in the synthesis and preparation of new materials.
Semiconductor industry: used for processes such as annealing and diffusion treatment of semiconductor silicon wafers.
Metal products industry: used for heat treatment, atmosphere regulation, and surface modification of metal products such as steel and aluminum alloys.
Ceramic industry: providing a stable high-temperature environment during the firing process of ceramics.
4. Components
The vacuum atmosphere furnace mainly consists of the following parts:
Furnace body: provides space for heat treatment.
Heating system: including electric heating elements or gas burners, used to provide heat.
Vacuum system: including vacuum pump, vacuum valve, vacuum measuring instrument, etc., used to extract gas from the furnace and maintain a vacuum state.
Atmosphere control system: used to control the composition and flow rate of gas in the furnace.
Other auxiliary systems, such as charging and discharging systems, air-cooled circulation systems, electronic control systems, pneumatic systems, water cooling systems, and material trucks, collaborate to complete the heat treatment process.
In summary, vacuum atmosphere furnace is a powerful and widely used heat treatment equipment. It provides ideal conditions for the heat treatment of various materials by creating a high vacuum environment and accurately controlling the composition and flow rate of the atmosphere.