Metal Matrix Composites for Lightweight, Nonmagnetic and Durable Diesel Engines

Substitution of the cast iron head and block with aluminum will significantly reduce the weight and magnetic signature of military and commercial diesel engines. However, aluminum cannot withstand the combustion chamber environment. Diesel engine experts agree that the headplate, is the weak link in all-aluminum head. Many engine companies are investigating the use of cast iron, or metal matrix composite (MMC) headplate inserts to address this problem. This program will develop a ceramic/aluminum headplate insert fabricated to net-shape via the Pressurized Shell Mold Casting (PSMC). Compared to cast iron, the MMC would exhibit superior elevated temperature mechanical properties and would be easier to integrate with an aluminum head. By combining low cost expendable tooling, solid freeform fabrication (SFF), low cost reinforcement and high volume pressure coating machinery, an MMC headplate insert may be cost competitive with cast iron. The program team can meet the five year TRP production requirement. Foster-Miller provides PSMC tooling methods and MMC expertise, Cummins Engine provides design, producibility guidance and a commercial engine application and MMCC provides high volume casting technology and a potential production source. Phase I will involve MMC properties characterization, production trials and a comprehensive producibility analysis. BENEFITS: A number of military and commercial diesel engine applications have been identified for MMC headplate inserts: commercial engines in the <200 hp range (Cummins B engine) non-magnetic diesels for Army systems, for pick-up trucks and marine craft, Coast Guard emergency pumps/generators, and light military trucks and ground vehicles. Cummins Engine has agreed to feed promising results directly into their ongoing lightweight engine internal R&D program.