visco-elastic constrained layer damping sheet
Decidamp® FDF is a specially formulated composite material comprising a visco-elastic polymer system laminated between two layers of polyester fabric. It is specifically designed to be used as a constrained-layer damping sheet in glass reinforced plastic (GRP) and fibreglass/foam sandwich constructions. Very high damping of structure-borne vibration can be achieved.
Decidamp FDF should be incorporated into the GRP structure at a stage where full thickness has been achieved. Once Decidamp FDF is in place, a further constraining layer of GRP, at 1/3 the full structure thickness is applied.
Decidamp FDF can be applied using two methods.
1. A “contact adhesive” is applied to both the GRP surface and the Decidamp FDF. Once the adhesive is completely dry the two surfaces can then be combined. A further layer of GRP to 1/3 the full structure thickness should then be applied.
2. With excellent wicking capability of the polyester fabric, Decidamp FDF is applied directly onto the wet GRP resin surface and smoothed into place to ensure a bubble free finish. The curing resin will penetrate into the fabric matrix ensuring a strong tie between Decidamp FDF and the GRP structure. Once in place, a further layer of GRP to 1/3 the full structure thickness should then be applied. No separate adhesive is required.