The high melting point and conductivity of tungsten wire make it an ideal heating element. The application of tungsten wire in automobile defrosting glass is mainly reflected in the electric heating defrosting system, especially in the defrosting function of rearview mirror, rear windshield and part of the front windshield.
1. The Role of Tungsten Wire
Tungsten wire is often used as an electric heating element due to its high melting point (about 3422°C), good conductivity and high temperature resistance. In automobile defrosting glass, tungsten wire is embedded or printed on the surface of glass or in the interlayer to form a heating grid or conductive film, which is used to quickly heat the glass to remove frost, fog or ice.
2. The Working Principle of Tungsten Wire for Glass Defrosting
Heating grid: Tungsten wire is processed into fine conductive lines and printed on the inner surface of the rear windshield in a grid shape. When powered, the current passes through the tungsten wire to generate heat, heating the glass surface, quickly melting frost or ice, evaporating fog, and keeping the glass transparent.
Uniform heating: The tungsten wire grid design ensures uniform heat distribution to avoid local overheating or insufficient heating.
Fast response: The conductivity and thermal response speed of tungsten wire are fast, and defrosting can usually be completed within a few minutes.
3. Specific Applications
Rear windshield: The most common application scenario is the defrosting system of the rear windshield. The tungsten wire grid is powered by the vehicle's power system (usually 12V DC), and the user starts the defrosting function through the in-car switch or automatic control system.
Front windshield: In some high-end models or cold areas, tungsten wire or similar conductive materials are also used for defrosting/defogging of the front windshield. Ultra-fine tungsten wire is embedded in the laminated glass to minimize the impact on the driver's line of sight.
Side windows and rearview mirrors: Similar technology may also be used on the side windows or rearview mirrors of some vehicles. Tungsten wire heating elements are used for rapid defrosting or defogging.