Tungsten wire is often used in glass heating processes (such as glass melting, forming or annealing) due to its unique physical and chemical properties. Its main characteristics are as follows:
1. High Melting Point: The melting point of tungsten is about 3422°C, which is much higher than the glass processing temperature (usually 1000-1600°C), so that it can maintain structural stability at high temperatures and is suitable for use as a heating element.
2. Good Thermal Stability: Tungsten wire is not easy to deform or volatilize at high temperatures, can maintain stable heating performance for a long time, extend service life, and reduce process maintenance costs.
3. High resistivity: Tungsten wire has moderate resistivity, can quickly heat up after power is turned on, and efficiently converts electrical energy into thermal energy, which is suitable for precise temperature control requirements of glass heating.
4. Corrosion Resistance: In a vacuum or inert gas (such as argon, nitrogen) protective environment, tungsten wire has strong resistance to oxidation and chemical corrosion, and is suitable for sealed or protective environments for glass processing.
5. Low Thermal Expansion Coefficient: Tungsten has a low thermal expansion coefficient (about 4.5×10??/K), which is similar to some glass materials (such as borosilicate glass), reducing stress or cracking caused by thermal expansion mismatch.
6. Mechanical Strength: Tungsten wire still maintains high strength at high temperatures, is not easy to break or sag, and is suitable for making heating elements with complex shapes.
7. Good Thermal Conductivity: Tungsten wire has a high thermal conductivity (about 173 W/m·K), which can evenly conduct heat and ensure consistent temperature distribution in the heating area. It is particularly suitable for glass annealing or molding processes that require high temperature uniformity.
8. Processability and Customization: Despite its high hardness, tungsten can still be processed into filaments, spirals or mesh structures through specific processes. This flexibility allows it to be customized according to the design requirements of glass heating equipment to optimize heating efficiency.
9. Environmental Adaptability: Tungsten filaments perform well in non-oxidizing environments, especially under vacuum or inert gas protection, with almost no volatile substances released, avoiding contamination of the glass surface and ensuring high purity and transparency of the finished product.
