![]() Thermal growth of oxides at the top coat/bond–coat interface and the decomposition of Al 2O 3-40%TiO 2 were found to be important degradation mechanisms leading to the spallation of coatings in the diesel engine and the petrol engine exploitation tests. In case of two strokes spark-ignition engine, during the combustion in the combustion chamber (CC), due to various reasons, cent percent combustion of the charge is not possible resulting in un-burnt hydrocarbons such as CO and HC. Phase stability of plasma sprayed Al 2O 3-40%TiO 2 was evaluated by means of X-ray diffraction method. Ceramic coating on various parts of an internal combustion (IC) engine provides excellent thermal barrier properties which are used in preventing the heat loss during the working cycle. ![]() Numerical calculation with Abaqus 6.7 finite element code was used to calculate temperature and stress variations in the coating throughout the test. ![]() The highest thermal fatigue resistance revealed TBC plasma sprayed with PSZ. Flame sprayed coatings were found more prone to damage than plasma sprayed ones. The extent of TBC deterioration experienced in thermal fatigue test was evaluated in the erosion test and SEM examinations. Two groups of double-layered thermal barrier coatings (TBC) were investigated: plasma sprayed with ZrO 2-8%Y 2O 3, Al 2O 3-40%TiO 2 or Al 2O 3-40%ZrO 2 top coats and powder flame sprayed with ZrO 2-30%CaO, Al 2O 3-40%TiO 2 and Al 2O 3-30%MgO. The emissions of other key pollutants (CO, unburned hydrocarbons and soot) were less affected under the part load conditions tested.The paper presents the results of investigation into the thermal fatigue resistance of thermal barrier coatings (TBC). By retarding combustion phasing slightly from the optimum, the NOx increase could be mitigated while still retaining most of the fuel consumption benefit, with the remaining benefit associated with reduced heat transfer during the remaining power stroke. The coating reduced heat transfer during combustion, leading to elevated engine-out NOx. The optimum coating applied across the full piston crown and bowl enabled up to 3% improvement in indicated thermal efficiency under idealised part load operating conditions. Coatings of varying features were tested in a bespoke thermodynamic single cylinder diesel engine instrumented for precision measurements of in-cylinder pressure, fuel consumption and legislated engine-out emissions. Benchtop laser flash measurements were undertaken to quantify coating thermal properties and provide the required empirical data for future thermal simulation. The new coating tested in this work was formed directly from the piston substrate material using an optimised plasma electrolytic oxidation process, with a silica top coat subsequently applied to entrap air within coating pores. Such swing coatings, of low thermal conductivity and low specific heat capacity, have recently been proposed to produce a dynamic thermal barrier layer that rapidly changes the temperature of the upper surface of the piston crown in response to the adjacent in-cylinder gas temperature. new opportunities for internal combustion engine applications. The work involved the development and on-engine testing of a new “thermo-swing” barrier coating for reduced wall heat transfer and increased thermal efficiency in future diesel engines utilizing aluminium alloy pistons. thermal barrier coatings on the performance of a spark- ignited gasoline engine was.
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