Experimental Evaluation of Novel Thermal Barrier Coatings in a Single Cylinder Light Duty Diesel Engine.
Objective The objective of this investigation is to improve the thermal properties of plasma sprayed thermal barrier coatings (TBC) for combustion engines. There is a need for further reduction of thermal conductivity and volumetric heat capacity. The negative effects of surface roughness and open surface porosity, typical for plasma sprayed coatings, should be minimized. Methodology To improve the thermal properties, four different measures were applied: 1. modification of the coating's microstructure by using suspension plasma spraying 2. application of gadolinia, a ceramic oxide material originated from aerospace industry 3. polishing of the coating to achieve low surface roughness 4. sealing of the porous coating surface with a polysilazane Six coating variants with different combinations of the applied measures were applied on the piston crown and evaluated in a single cylinder research engine.