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Most piston rings and metallic sealing rings for modern application where running conditions are severe, require some form of coating to minimise abrasion and corrosion. The piston ring coating improves the life of engine as well as fuel efficiency. ...Wear test of the coating was conducted on pin on disc machine under dry conditions. The wear rate was calculated using mass loss methods on an electronic balance having least count of 1× 10−4 g. ...The wear rate of the coating was found to be increased with increase in load as well as sliding speed for the ion plating with the counter body of tungsten carbide but in the case of ion plating with the HCS & MS it is found to be decreased.

A discussion is presented on the various important features which need to be addressed in the design of viable thermal barrier coatings. The most economical way to ensure increased lifetime and operational safety of diesel engine components is to use a coating in order to improve surface properties. ...The most economical way to ensure increased lifetime and operational safety of diesel engine components is to use a coating in order to improve surface properties. By comparing the surface material properties required for engine operations and the properties of coating systems achieved until now, it is evident that the fracture toughness must be improved. ...By comparing the surface material properties required for engine operations and the properties of coating systems achieved until now, it is evident that the fracture toughness must be improved.

Our approach is to apply a DLC coating on the piston running against an aluminum-390 bore thus eliminating the iron liners in a standard piston/bore system. ...Experimental data, using a pin-on-disk tribometer under unlubricated test conditions, indicate that the performance of the DLC coating against aluminum 390 exhibits superior friction resistance compared to aluminum-390 against cast iron; the latter material couple representing the materials currently being used in production for the piston/bore application. ...Moreover, by thermally cycling the DLC coatings we show that improved friction and wear properties can he maintained to temperatures as high as 400°C.

This Paper presents comparative analysis of heat release in base line and insulated (Piston crown with plasma sprayed zirconia coating) diesel engine. The coating system affects the fuel consumption, the power and the combustion efficiency, pollution contents and the fatigue lifetime of engine components. ...Experimental research of insulated diesel engine incorporating thermal barrier coating (TBC) has produced controversial result. Some publications report that engine efficiency increases with insulation, while others argue that efficiency decreases. ...Several disadvantages such as producing nitrogen oxides also exist when a coating system is used. In this Paper, all effects, advantages and disadvantages of thermal barrier coatings are investigated based on experimental result.

Thermal barrier coatings (TBCs) were used to simulate adiabatic engines with the intention not only for reduced in-cylinder heat rejection and thermal fatigue protection of underlying metallic surfaces, but also for possible reduction of engine emissions. ...The insulation of the combustion chamber with this coating, which is ceramic based, influences the combustion process and hence the performance and exhaust emissions characteristics of the engines. ...A plasma sprayed thermal barrier coating was deposited on top of a piston for a Diesel engine and its effect on the engine performance is studied.

Ni-SiC coating commercially known as NIKASIL, is the most commercially used coating in automobile’s/aero IC engines. ...Present study provides an oxide namely Yttria Stabilized Zirconia (YSZ) reinforced Nickel-Cobalt based wear-resistant and fuel-saving composite coating replacing the existing NIKASIL coating used in automobile engines. The said wear-resistant coating was developed using simple electrochemical deposition method. ...The deposition conditions were optimized and the developed coating displayed a microhardness of 500 ± 30 KHN50gf. The wear loss of Ni-Co-YSZ coating was observed to be 6.7 × 10-7 mm3/m against EN31 hardened steel.

Plasma electrolytic oxidation (PEO) coating is considered as a hard ceramic coating which can provide a dimpled surface for oil retention to bear the wear and reduce the friction from sliding piston rings. ...Five different lubricating oils and two different loads were applied to do the tribotests and the COFs of a PEO coating were studied. The results show that the PEO coating indeed had a lower COF in a lower viscosity lubricating oil, and a smaller load was beneficial to form the mixed and hydrodynamic lubricating regimes earlier. ...When tested with a very high viscosity of oil, the counterpart material had a significantly less wear, which may indicate that such kind of oil would provide a piston ring with a better protection against the ceramic coating. Thus, a proper selection of lubricating oil for PEO coating would be a decisive factor for balance between reducing friction loss and piston ring wear in an IC engine.

The approach consists in the definition of a thicker equivalent coating material that reproduces the thermal behavior of the real thin coating. The calculations are performed using a commercial 3D-CFD software for a Diesel engine considering two configurations: conventional metallic piston and coated piston top. ...The main idea when coating the combustion chamber with these materials is to obtain a reduction of the temperature difference (thermal swing) between gas and walls during the engine cycle and minimize heat losses. ...Nevertheless, the new generation of insulating coatings is posing challenges to numerical modelling, as layer thickness is very small (~100 μm).

Thermal Barrier Coating is an attractive and promising method in providing thermal insulation for the engine components due to its good thermo-mechanical properties. ...This research has been executed on three cylinder naturally aspirated diesel engine to understand the effect of the ceramic compound coating Yttria-Stabilized Zirconia, on engine performance and emission characteristics. This investigation compares the performance & emission characteristics of two different configurations namely, Engine Build I (Baseline Engine) and Engine Build II (Ceramic coated on cylinder head (incl. valves) of the Engine). ...Test results revels, that Ceramic coating on Cylinder head produce a reduction in fuel consumption, delivers higher performance and better emission characteristics.

A possible approach for reducing the thermal exchange requires the use of thermal barrier coating (TBC) made by materials with low thermal conductivity and good thermo-mechanical strength. ...In this work, the effects of a ceramic coating for thermal insulation of the piston crown of a car diesel engine are investigated through a numerical methodology based on finite element analysis. ...The loads acting on the piston are considered both separately and combined to achieve a better understanding of their mutual interaction and of the coating effect on the stress state. The thermal analysis pointed out a decrease of temperature up to 40°C in the upper part of the piston for the coated model.

Using this benefit to reduce side forces by a longer connecting rod, the full friction reduction potential is achieved by a combination with a new low friction carbon based coating on the piston pin. The new coating shows best-in-class performance in terms of friction and high temperature resistance compared to currently available pin coatings. ...A piston compression height reduction in combination with carbon based piston pin coatings is enabling advancements in both demands. MAHLE implemented a new innovative metal joining technology by using laser welding to generate a cooling gallery. ...The new coating shows best-in-class performance in terms of friction and high temperature resistance compared to currently available pin coatings. The shorter compression height also results in reduced oscillating masses. This can be used for further weight reduction in the whole drivetrain, which allows the implementation of further systems for better fuel efficiency, e.g. waste heat recovery, without reducing payload.

This paper discusses the implementation of insulation or thermal barrier coating (TBC) as a means of reducing local oil viscosity and power cylinder friction in internal combustion engines with minimal side-effects of increased wear.

The cylinder of the aluminum engine block without iron sleeve was coated directly with thin thermal barrier coatings of zirconia and chrome oxide. The cylinder head and valve face and the piston crown were also coated.

However, the ceramic structure of most phosphor coatings might introduce an error, due to its thermal insulation properties, when being exposed to rapidly changing temperatures.

This paper aims to simulate how the piston top’s thermal barrier coating affects the engine’s thermal efficiency and emissions. Accordingly, a Thin-wall heat transfer model in AVL Fire software was employed. ...The effects of increasing the piston top surface temperature, comparing different thermal barrier coating material, were simulated at the engine’s rated power operating point, so as the piston top’s surface roughness. ...Comparing among the different coating materials, SiRPA (quartz reinforced porous anodic alumina), Zirconia (zirconium oxide), and YSZ (yttria-stabilized Zirconia), SiRPA was found to be the most effective one in term of thermal flux reduction, which could promote ITE by 0.8%.

This paper analyzes the influence of a catalytic coating of the combustion chamber on combustion, emission formation and fuel consumption. For this purpose, test runs with a production 2.0-liter, 4-cylinder, 4-valve, double overhead camshaft (DOHC), port fuel injection (PFI) gasoline engine were performed. ...The various possible benefits of the catalytic coating mentioned above were separated by different engine setup combinations. The coated configuration was optimized in terms of its part load performance with special focus on fuel consumption and emissions, and thereafter compared to the baseline engine configuration. ...This leads to a steeper and higher pressure gradient and hence better combustion stability under lean conditions. The coating and especially the possibility to change maximum brake torque (MBT) spark timing due to the changed combustion characteristics caused by the coating also affect NOX and HC emissions at some load conditions.

This study looked into the application of active thermal coatings on the surfaces of the combustion chamber as a method of improving the thermal efficiency of internal combustion engines. ...The active thermal coating was applied to a production aluminium piston and its performance was compared against a reference aluminium piston on a single-cylinder diesel engine. ...A detailed energy balance approach was employed to study the thermal behaviour of the active thermal coating. In general, improvements in indicated specific fuel consumption were not statistically significant for the coated piston over the whole test matrix.

This paper presents a comprehensive study on using MO (Mahua oil) as fuel effectively in a diesel engine by adopting emulsification and TBC (Thermal Barrier Coating) techniques. A mono cylinder diesel engine was used for the study. Initially trials were made on the engine using neat diesel (ND), Neat Mahua oil (NMO) as fuels. ...Finally thermal barrier coating of 0.2 mm was made on the piston, valves and cylinder head of the engine using the ceramic power of Al2O3 and the engine was tested using NMO and MOE as fuels in the TBC engine.

Thermal Barrier Coatings (TBCs) selectively manipulate the in-cylinder surface temperature, providing an avenue for improving thermal and combustion efficiency. ...This study follows prior work of authors with Yttria Stabilized Zirconia, which systematically engineered coatings for HCCI combustion. Herein, a modeling study was used to assess the impacts of various TBC material properties, e.g. density, thickness, and thermal conductivity on the temperature swing effect. ...A novel TBC formulation was developed, leverages a class of materials that, to the author’s best knowledge, have not been used as a thermal barrier coating previously. A systematic experimental investigation was carried out using single-cylinder research engine.

Heat transfer models have been developed for diesel engine performance with and without thermal insulation coating that is incorporated in the simulated program. A wall heat transfer model has been formulated and developed and coupled along with the above combustion and gas-wall heat transfer model to predict the effect of varying wall temperature on combustion, heat release, heat transfer and overall performance of a low heat rejection direct injection diesel engine.