Piston is considered to be one of the most important part of internal combustion engine. Piston is used to deliver thrust via connecting rod to the main shaft of the engine. Normally it is made of cast iron which bears high gas pressure and has damping property. The main objective of this chapter is to perform structural and thermal analysis of MgZrO3 top surface ceramic coated piston. Piston made up of gray cast iron coated with ceramic material (MgZrO3) which is bonded by special material (NiCrAl) is designed by machine design approach to determine the dimensions of the piston and Finite Element Analysis (FEA) was performed using ANSYS 17.1. The pressure of the 5 N/mm2 was applied at top land of piston. An equivalent Von misses stress in ceramic coated piston was found less in comparison to uncoated piston. Thermal analysis of both coated and non-coated piston was performed.
TopIntroduction
Piston is an integral part of internal combustion engine. It helps to produce power and it is subjected to high temperature and pressure. The life of components like piston, piston pin, connecting rod, crank and other internal part of piston is affected by high temperature and pressure. Piston is a cylindrical part in cylinder which reciprocates in it. It is either moved by the mixture (air and fuel) or it moves the mixture which enters inside the cylinder of I.C. engine. Function of piston is to receive thrust due to combustion of mixture and then transfer thrust to the crankshaft via connecting rod which in turn runs the engine shaft. It also transferred a large amount of heat from the combustion chamber to the cylinder walls.
Cerit (2014) in his research article titled “Temperature and thermal stress analyses of a ceramic-coated aluminum alloy piston used in a diesel engine” has determined temperature and thermal stress distributions on a plasma-sprayed and magnesia-stabilized zirconia coated aluminum piston crown. It improves the performance of a C.I. engine. Effect of the coating thickness on temperature and thermal stress distributions was well investigated, including results comparison with uncoated piston. Temperature and thermal stress analysis was performed for various coating thicknesses from 0.2 to 1.6 mm. Temperature at the coated surface is found to be significantly higher than that of the uncoated piston. It observed that the coating surface temperature increases with decreasing rate of coating thickness. For 1 mm thickness coating on piston it increases 64.3% higher temperature sustainability. The normal stress on the coated surface decreases with increase in coat thickness. The higher combustion chamber temperature achieve by coating results with better thermal efficiency of the engine.
Chan (2000) in his article titled “The effect of thermal barrier coated piston crown on engine characteristics”, has investigated the use of ceramic components in reciprocating engines. Ceramic components are now in service, mainly for enhancing cylinder heat absorption on thermal coating. They work on a low heat rejection engine. Experiments were conducted on a three-cylinder SI engine with piston crowns coated with layers of ceramic, which is composed of Yttria-Stabilized Zirconia (YSZ). Measurement and comparison of engine performance has been done for particular fuel consumption, made before and after the application of YSZ coatings on the piston crowns.
Hejwowski (2002) in research article entitled “ The effect of thermal barrier coatings on diesel engine performance” has performed experimental study to know effects of thin thermal barrier coatings on the performance of a diesel engine. The results obtained from the analysis of thermally insulated pistons of engines were compared with the base (existing) engine data. Engine trials demonstrated good properties of both coating systems. The temperature and stress distributions on the pistons were evaluated analytically by means of the Cosmos/Works FEM. Results of a road test on a gasoline-engine-driven car are also reported. They concluded that the performance of the modified engine-driven car was found satisfactory and ceramic coating did not produce observable knocking in the engine, no significant wear of piston skirts or cylinder liners were reported.
Pierz (1993) in research article “Thermal barrier coating development for diesel engine aluminum pistons” determined the Specific outputs of some diesel engine applications have applied thermal loadings in excess on aluminum-piston alloys. He has evaluated Thermal barrier coatings to find the component durability to acceptable levels and also giving a means of lowering heat rejection. The use of a finite element model to analyze these thermal barrier coating systems which include the impact on material properties, coating thickness, residual stress and boundary conditions was discussed in this research article. The resulting temperature and stresses, together with material strength were found. The main cause of failure of coating was found to be due to low cycle fatigue arises due to localized yielding when the coating is hot and in compression.