A metal decide the performance and limit of a machine. We are often interested in finding which metal is used in manufacturing of an IC engine and why. In manufacturing of an engine we have to use those metals which can handle the pressure and temperature of the engine and should be cheap in price. Today I am going to tell you about the metals which is used in IC engine and there method of manufacturing.
Cylinder is made by high grade cast iron because it is in direct contact of combustion gases. Cast iron has high compressive strength to handle the pressure and temperature. It is made by casting and usually cast in one piece.
The main function of cylinder head is to seal the cylinder and it should be light in weight. So cylinder head is usually made by cast iron or aluminum. It is made by casting or forging and usually in one piece.
Piston is prime mover in engine so it should be light. It is in direct contact with combustion temperature and pressure so it should has high strength to handle this pressure. So generally piston is made by cast iron but sometime it is made by aluminum alloy. Usually it is made by casting.
Piston ring is usually made by fine grain of cast iron which has high elasticity and it is not affected by the working pressure. Sometime piston rings are made by alloy spring steel. It is made by forging.
Connecting rod transmits the power to crankshaft. It should have high strength. So it is made by alloy steel but in small engine it is made by aluminum to achieve lighter weight. It is made by forging.
Inlet valve and Exhaust valve:
Inlet valve admits the air and fuel into the cylinder. It is usually made by silicon chrome steel with about 3% carbon. It is made by forging.
Exhaust valve discharge the exhaust gases. It is made by austenitic steal. It is also made by forging.
Crankshaft converts the reciprocating motion of piston into rotary motion. It should have high tensile strength. So the crankshaft made by high tensile steel or sometime by cast iron. It is usually made by forging.
Piston pin is made by hardened steel so it can support and allow to connecting rod to swivel. It is usually made by forging.
Engine bearing should have lubricant property and strength to withstand in moving load. So its half is made of steel or bronze back to which a lining of relatively soft bearing material is applied.
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