Vacuum heat treatment electric furnace used in the experiment

The vacuum heat treatment electric furnace used in experiments is an advanced equipment that combines vacuum technology and heat treatment technology. By heating and cooling materials in a vacuum environment, it can achieve heat treatment effects without oxidation, decarburization, or carburizing. It also has advantages such as bright surface purification, small deformation, high qualification rate, energy saving and safety. The following is an explanation from four dimensions: working principle, core functions, application areas, and device characteristics:

1. Working principle: Heat treatment technology in vacuum environment
The vacuum heat treatment electric furnace uses a vacuum system to reduce the pressure inside the furnace chamber to low, medium, high, or ultra-high vacuum (usually 1.33 × 10 ⁻³ Pa to 1.33 × 10 ⁻⁵ Pa), and heats and cools the material in an oxygen deficient environment. The core principles include:
Avoid oxidation and decarburization: In traditional heat treatment, metal reacts with oxygen and water vapor in the air to form an oxide film or decarburization layer, while a vacuum environment can completely eliminate such reactions and maintain a smooth surface of the material.
Defatting and degassing: Vacuum can remove phosphorus chips, grease, and adsorbed gases from the surface of the workpiece, improving material purity.
Rapid temperature rise and fall: Through efficient heating elements (such as molybdenum, tungsten, graphite) and water cooling systems, rapid temperature rise (up to 2200 ℃) and cooling can be achieved, shortening the process cycle.

2. Core function: Covering the entire heat treatment process chain
This device supports almost all heat treatment processes, including but not limited to:
Metal heat treatment
Annealing: Relieve stress and improve tissue uniformity (such as vacuum annealing of high-speed steel cutting tools at 500-650 ℃).
Quenching: High hardness martensitic structure is obtained through gas quenching (N ₂/Ar), oil quenching, or nitrate quenching (such as oil quenching at 1000-1050 ℃ for mold steel, with a hardness of 52-55 HRC).
Tempering: Adjust the balance between hardness and toughness (such as vacuum tempering of bearing steel at 150-200 ℃ to reduce brittleness).
Carburizing/nitriding: achieving surface hardening in a vacuum+active gas (C ₂ H ₂/N ₂) environment (such as vacuum carburizing of stainless steel at 900-950 ℃, increasing surface hardness by 2-3 times).
Synthesis of Ceramics and Composite Materials
Pressureless sintering: preparation of high-density ceramics (such as Al ₂ O3 sintered at 1600-1700 ℃, relative density ≥ 99%).
Hot pressing sintering: By applying external pressure to promote densification (such as hot pressing at 1700-1800 ℃ for Si ∝ N ₄, the bending strength can reach 800-1000 MPa).
C/C composite materials: Preparation of lightweight and high-temperature resistant materials (for rocket nozzles) through impregnation carbonization cycles (1000-2200 ℃).
Preparation of Semiconductors and Nanomaterials
Crystal growth: such as silicon single crystal direct pull method (1420 ℃) used for integrated circuit substrates.
Thin film deposition: High purity thin films (such as Al mirrors, Si ∝ N ₄ MEMS devices) are deposited under vacuum using PVD/CVD.
Nanoparticle synthesis: such as vacuum evaporation of silver nanoparticles (1000-1100 ℃) with a particle size of 5-20 nm.

3. Application area: Cross industry material research and development platform
Aerospace: Vacuum annealing of titanium alloy (700-900 ℃) eliminates work hardening and improves plasticity; C/C composite material sintering is used for rocket nozzles.
Electronic information: Semiconductor crystal growth (silicon, GaAs) and thin film deposition (Al, Si ∝ N ₄) for the preparation of integrated circuits and MEMS devices.
New energy: Vacuum sintering of fuel cell electrode materials to enhance conductivity and corrosion resistance.
Biomedical: Vacuum sintering of bioceramics (such as ZrO ₂) to prepare artificial joints, avoiding impurity contamination.
Automotive industry: Vacuum quenching of mold steel improves wear resistance and extends service life.

4. Equipment features: High precision and high reliability design
Vacuum sealing structure: using airtight welding furnace body to reduce the chance of leakage and ensure the working vacuum degree.
Low voltage and high current heating: Avoid glow discharge to ensure safety.
High temperature resistant materials: The heating and insulation layer is made of tantalum, tungsten, graphite, etc., which are resistant to high temperatures and have low steam pressure.
Automated control: PID intelligent temperature controller supports multi-stage program temperature control (± 1 ℃ accuracy), equipped with over temperature protection and data storage functions.
Safety design: The water cooling system prevents overheating of the furnace body, and the explosion-proof device addresses the risk of flammable gases such as hydrogen.