Paris – Bayer MaterialScience is presenting a newly developed sandwich material based on the Baypreg polyurethane spray system at the JEC Composites fair in Paris, 27-29 March.
BMS says the material is very well suited for diesel engine enclosures. The finished component is 35 percent lighter and 30 percent less expensive than its steel-and-aluminium counterpart, the company claims. The prototype is being honoured with the 2012 JEC Innovation Award.
The enclosure is located beneath the train’s passenger compartment and above the tracks. It must be able to withstand high mechanical loads because it has to protect the engine from rock impacts. It also has to have good chemical resistance and needs to comply with strict fire protection requirements. BMS says its composite material featuring the polyurethane spray system easily meets all of the requirements mentioned above.
The sandwich structure is based on a honeycomb core covered on the top and bottom with glass fibre mats. It is sprayed from both sides with the Baypreg system, which contains the flame retardant and, optionally, cut glass fibres.
The still moist composite is placed in a mould, where it is preferably pressed at a temperature of 130 °C. The polyurethane system reacts and foams slightly, binding the components together firmly and permanently, according to BMS.