IMPROVEMENT OF SPOT WELDABILITY IN VIBRATION DAMPING STEEL SHEET.

Vibration damping steel sheets (VDS) have good damping capacity, and they are applied for materials such as automobile bodies to reduce their noise. Conventional VDS cannot be attached by spot welding because the core viscoelastic layer acts as an electrical insulator. Usually this difficulty is overcome by providing a bypass circuit which acts as a short circuit. In the case of parts such as oil pans which require only a few weld spots, this method can be used efficiently. However, with parts requiring many weld spots such as body panels, it makes the weld operation very difficult to set up a short circuit device. This was achieved by laminating electrical conductive film between steel sheets.