Damping Property of Carbon Fiber Reinforced Plastic for Noise/Vibration/Harsh of Steering Column Support Assembly

Composite materials have penetrated into structural applications within the automotive industry, replacing traditional materials to reduce weight and then to improve fuel efficiency and to meet emission regulation. For some composite structural components, a significantly lower mode value compared to metal components can be accepted with an equivalent or better noise/vibration/harshness (NVH) performance, because, for composite materials, with different characteristics and much higher damping value compared to metal materials, a more sophisticated definition is required. An experimental investigation for mode definition of carbon fiber reinforced plastic (CFRP) steering column support assembly is discussed. Two kinds of composite steering column support assembly were manufactured, one is carbon fiber (CF) reinforced polyamide66 (PA66) with high mechanical properties, the other is glass fiber (GF) reinforced polyamide66 (PA66) with lower properties. The NVH test was carried out for these two components, and then the steering system mode requirement was defined by the test result. The new defined mode requirement obtained in the experiment showed good agreement with steering system mode analysis and test. By comparing the defined system mode requirement of composite component with that of the steel component, the effect of damping property of this composite material of the component can be clearly shown, which is over 21% percent on the NVH performance.