Development of Endurable Thermal Barrier Coatings for Diesel Engine Specific Heat Reduction

The future generation of both military and commercial diesel engines will operate at significantly higher temperatures and pressures than today’s engines. The future combat system diesel engine operating parameters demand significant design improvement of power cylinder insulation. Increased cylinder pressure and reduced cooling requirements, heat energy recovery in the exhaust gas by turbocharging and turbo-compounding will likely be incorporated. Thus significantly improved engine fuel efficiency, performance, and reliability will be achieved. As temperature and pressure loads for base materials in diesel engines are pushed to the maximum limit, further improvements in engine life time can only be realized by changing existing component substrate or thermally protecting existing hardware by applying protective coatings. Use of Thermal Barrier Coatings (TBCs), show numerous advantages such as higher allowable combustion temperature and reduced heat losses to the cooling fluids (water and oil). This Phase II effort will extend the research and development base generated from the Phase I work to both prove and expand on new endurable composite TBC technology. Given the opportunity, we have demonstrated in a military FCS type multi-cylinder engine the feasibility of newly developed composite TBCs for power piston, cylinder liner, cylinder head firedeck, and exhaust hardware. We have experienced successes on nearly all of the engine hardware except for the exhaust valve tulip area. The engine on the first trial demonstrates very good engine performance. We believe given the opportunity presented through a Phase II program, we have put together a research team that not only will solve the valve tulip insulation issue, but improve and optimize all TBCs for the engine to further improve engine performance and meet all commercial and military Reliability, Accessability, Maintainability and Durability (RAM-D) goals in a cost effective manner.