Damping Composite Sheet for Noise Control

With regard to the reduction of engine noise caused by cars, which is one of important technology in the automobile industry, vibration damping composite steel sheet has been developed. This sheet is made of a layer of visco-elastic synthetic resin sandwiched by 2 sheets of steel. The excellent vibration damping of the sheet is shown by its “loss factor” (η) ≧0.5 at 80°C and approximately 3 dB (A) noise reduction when applied to the engine cover of a portable generator, indicates that this steel sheet has application to automobile parts in which noise reduction should be considered. This paper describes the manufacturing process and some basic properties of this sheet followed by its applications.