Pure tungsten wire or doped tungsten wire is usually preferred for glass heating because of its high melting point, high temperature resistance and excellent stability. It is necessary to select the appropriate tungsten wire specifications according to the glass type, heating temperature and equipment design, and ensure that vacuum or inert gas protection is used to extend the life. For more specific suggestions and purchases, please contact CTIA GROUP (sales@chinatungsten.com).
1. Why Choose Tungsten Wire?
1.1 High Melting Point: The melting point of tungsten is 3422°C, which is suitable for the high temperature environment of glass heating (the softening point of glass is usually 500-1500°C).
1.2 High Temperature Oxidation Resistance: Under the protection of vacuum or inert gas (such as nitrogen or argon), tungsten wire can withstand high temperature for a long time without oxidation.
1.3 Good Thermal Conductivity and Electrical Conductivity: Tungsten wire can heat up quickly and transfer heat evenly, suitable for precise temperature control.
1.4 Mechanical Strength: Tungsten still maintains good strength at high temperatures, suitable for making thin wires or heating elements with complex shapes.
2. Material Selection of Tungsten Wire for Glass Heating
2.1 Pure Tungsten Wire: Suitable for most glass heating scenarios, the purity is usually above 99.95%, the cost is low, and it is suitable for vacuum or inert gas environment.
2.2 Doped Tungsten Wire: Tungsten wire doped with potassium, silicon, and aluminum (such as WAL) has better creep resistance and longer service life, suitable for high-load or long-term operation equipment.
2.3 Tungsten-Rhenium Alloy Wire: Tungsten wire doped with rhenium (3%-26%) has higher ductility and thermal shock resistance, suitable for scenarios requiring frequent switching or complex processes, but the cost is higher.
3. Considerations for the Use Environment
3.1 Atmosphere Protection: Tungsten wire is easily oxidized at high temperatures in the air and must be used in a vacuum or inert gas (such as argon, nitrogen) environment. Glass heating equipment is usually designed with a sealed chamber or gas protection system.
3.2 Temperature Range: According to the type of glass (such as borosilicate glass, quartz glass or ordinary soda-lime glass), select the appropriate tungsten wire specifications and power to ensure that the heating temperature matches the softening point of the glass.
3.3 Current and Resistance: The resistance of tungsten wire increases with increasing temperature, and a suitable power supply and control system must be designed to stabilize the current.
4. Other Considerations
4.1 Surface Treatment: The surface of tungsten wire must be smooth and crack-free to reduce the risk of local overheating or breakage.
4.2 Installation and Fixation: Tungsten wire is easy to deform at high temperatures and needs to be fixed with high-temperature resistant ceramics or molybdenum clamps to avoid contact with glass or metal parts.
4.3 Life and Maintenance: Regularly check the aging of tungsten wire (such as brittleness or surface oxidation) and replace it in time to ensure heating efficiency.
