Cylinder Housing of Glass Fiber-Reinforced Phenolic Resin
Researchers at the Fraunhofer Institute for Chemical Technology (ICT) have developed a cylinder housing made from fiber-reinforced plastic for a single-cylinder research engine. The cylinder housing weighs approximately 20% less than the corresponding aluminum counterpart. The material used is a glass fiber-reinforced phenolic resin with a fiber loading of 45 percent. Regions subjected to very high thermal or mechanical stresses such as the cylinder liner, for instance, have metal inserts. Moreover, the scientists have adjusted the geometry so that the thermal stress on the plastic remains as low as possible.
Plastic engine blocks were already developed in the 1980s. At that time, however, it was not possible to produce the components in large quantities. Injection molding the engine blocks from a thermosetting powder is now expected to make this possible. According to the information provided, this manufacturing method is considerably more economical than production of aluminum engines. In addition, less finishing work is required.
The engine has already been tested successfully on a test stand and achieved the same output as conventional engines. Furthermore, the plastic engine is significantly quieter than its metal counterparts. According to the Institute, the plastic engine even radiates less heat to the surroundings than the aluminum engine.