Piston Of Automotive Vehicles: Material Selection And Properties

Details of Role and Properties of Component Selected

Write an essay on Piston of Automotive Vehicles.

The material selection in the automotive industry requires the fulfillment of many requirements. Some of these requirements are of safety, light weight, performance, cost and some of these are as per customer’s requirement. The piston of a automotive vehicle is a very important part and the material selection for this requires the consideration of many factors like melting point, cost, friction coefficient etc.
The material of a piston may be either aluminum alloy or cast iron depends on the type of automotive vehicle. The cast iron piston requires more attention towards its thermal properties and gives a good performance whereas the aluminum material is preferred for the best performance. The aluminum alloy material is preferred when a speed requirement of more than 6 m/s and the cast iron material piston is preferred when the speed requirement is less than 6 m/s. The aluminum alloys has a higher heat transfer coefficient and thus does not have any high heating problem.

The piston of an auto vehicle converts the pressure force into the movement of crank shaft. Piston begins, animates and stops in for every half rotation of the crank shaft. The inertial force depends on the piston and less idleness endowments for high pressure. In the midst of operation of the piston, a temperature slant of around 150 K from the pioneer of the heap to its base is experienced. So additionally it needs to reinforce chamber evolving rings. The piston must be strength enough, and reinforced to meet the requirements of withstanding at higher temperatures. The friction of the piston material, weight and the long length skirting should be very less. The components of a cylinder more or less are;
The piston should have space for the oil and seal inside the piston.
It should be able to transmit power through the gudgeon pin.

DETAILS OF ROLE AND PROPERTIES OF COMPONENT SELECTED
Component selected = Engine piston
Role: Provides the necessary power by burning fuel and then removes the combustion products.
Material of piston: Aluminum alloy
Mechanical properties of aluminum alloy
Hardness    96
Ultimate tensile strength    315 MPa
Tensile yield strength    278 MPa
Modulus of elasticity    69 GPa
Shear strength    208 MPa
Machine ability    50%
Thermal properties of material
Specific heat capacity    896 KJ/kg.0C
Thermal conductivity    167 W/mk
Melting point    582 – 652 0C
Physical property

Density = 2700 kg/m3
Chemical properties
Solution temperature    529 0C
Aging temperature    160 0C
Electrical property
Electrical resistivity = 3.99e – 006 ohm-cm

ADVANTAGES OF ALUMINUM ALLOY OVER CAST IRON MATERIAL
•    Heat transfer coefficient of aluminum is nearly 3 times of CI. In this manner aluminum combination piston has less variation in temperature of the piston head and piston rings.
•    The density of aluminum speaks the truth 33% that of cast iron. Along these lines light weight development and less idleness powers.
•    Good tensile strength.
•    Produces high speeds greater than 6 m/s.
•    High efficiency.
•    High power production.

DISADVANTAGES OF ALUMINUM ALLOY OVER CAST IRON MATERIAL
•    Higher cost than cast iron material.
•    Not best suitable for heavy load vehicles.
•    High coefficient of linear expansion.

ADVANTAGES OF CAST IRON     OVER ALUMINUM ALLOY MATERIAL
•    Wear quality of cast iron piston is more.
•    Cast iron pistons have higher quality. As temperature builds, the quality of aluminum combination piston declines rapidly. Because of higher quality, it is conceivable to give dainty segments to the parts of cast iron piston.
•    In light of higher coefficient of warm development aluminum, aluminum amalgam pistons require more leeway between the chamber divider and piston rings.
•    Low cost.
•    Low coefficient of linear expansion.

DISADVANTAGES OF CAST IRON OVER ALUMINUM ALLOY MATERIAL
•    Heavy weight material i.e. increases the engine weight.
•    Not suitable for high speed vehicles.
•    Low efficiency.
•    Low power generation.

ANALYSIS
The complete piston social affair holds around 52-58% of power consumption of whole setup. For an ordinary piston with three rings, first ring with 50% weight ring for the friction work, second piston ring is 30-35% and the third piston ring is only 10-15% of the oil control. Pistons are given amplified cushions or skirt ribs from which material is uprooted to bring the chamber weight inside required quality. Piston head (crown) approach is uncommonly essential for the fuel injection and ignition of the fuel injected during the start of the power stroke. The straightforwardness, low execution engines usage level top chambers with breaks cut in it to give valve head flexibility. Chambers for first class engines have raised twists to widen weight. The head of the piston made have high strength so that it can be withstand with the high ignition temperature and the weight transfer. Piston rings similarly work as sharp edges to trade hot to the engine oil. The aluminum cylinders are created using the tossing method.

PISTON MATERIAL COMPARSON WITH OTHER MATERIALS
The piston material must possess properties like grand hurled point of confinement, higher strength, amazing strength to surface scratched zone to reduction skirt and ring-score wear, immense warm conductivity to keep down piston temperatures, and a for the most part low warm expansion to have a base piston to-chamber breathing room. To fulfill low reacting attributes of the piston in a smart engine, the chamber should be lighter, and therefore aluminum compound is grabbed the chance to cast iron and steel. In any case, to keep up the steadfast system for cast presses, the extents of the aluminum structures must be more essential, thus off-setting the considerable position of daintiness to some degree. The aluminum alloy has a combination of copper, silicon, nickel etc.
The hot strength of unadulterated aluminum, with 4.5% copper and 3% nickel, of 13% silicon compound, and of 20% silicon mix. At 0 degree Celsius temperature the aluminum alloy material is the most grounded, the 23%-silicon compound is of the lowest strength, and the 12%-silicon mix is in within. At higher temperature their hot quality diminishments however the rate of decay of the quality for the 23%-silicon blend is not as much as that of the other two and at around 553 K its hot quality in better as the other two mixes. Aluminum compound is a vastly enhanced conductor of warmth than cast iron and practices 3.3 times more prominent smoking in for a specified period in comparison with the CI. Regardless, the better hot diffusing nature of aluminum composite decreases the best piston head working temperature, which is by and large in the level of 530 to 575 K for composite chambers and 400 to  500 0C cast iron chambers.

PERFORMANCE OF ALUMINUM PISTONS
Elite, exceptionally charged traveler auto diesel motors are for the most part seen as the touchstone for Al pistons as the warm also, mechanical piston burdens in the burning chamber are immense to the point that motor creators are concerned the lightweight material may in the long run come up short. Commonly it is the dish edge where splits start. In this manner the first intelligent measure is to fortify this zone. It is the material itself which recommends a arrangement: Although the throwing procedure has as of now been enhanced to abuse the most extreme cooling rate which still results in an impeccable item, the cooling is still too moderate for a greatest material quality at the dish edge.
                    
IMPROVED HEAT TRANSFER FOR ALUMINUM MATERIAL
As the measure of heat is so awesome in the dish territory, a second result is to enhance the heat dispersal from the piston bowl and edge. A compelling method for doing this is to position the cooling display higher up and in this way near the dish edge and top ring. The cooling impact at the dish edge and first ring woods is subsequently enhanced by more than 10%, at the pin bore the change is around 5%. Then again the state of the exhibition can be adjusted to the application. While this is not excessively complex from a configuration point of perspective, it is very difficult to control the throwing procedure to guarantee that there is sufficient material of steady cavity free quality between the dish and the display and/or between the exhibition and the cast in Al fin embed. The principal creation use of the raised exhibition piston keeps the piston at temperatures much lower than the satisfactory furthest reaches of 400 °C. Under the same conditions, a standard piston's dish edge anxieties are 43% higher and its temperature comes to 440 °C, near the softening purpose of the to begin with metal stages in the lattice. Depending on the application necessities the ideal display position and outline can be adaptable characterization.

RESULT
The piston of an engine is made of normally aluminum alloys, cast iron, and forged steels. The cast iron was used primarily for making pistons but now a days the aluminum alloys are used for making the pistons because of their enhanced properties and light weight properties. The performance of the aluminum alloy piston can be further improved. The speed varies for both the materials i.e. cast iron and the aluminum alloy. The energy consumption in the aluminum alloys due to friction is about 30-40% lesser than that of the cast iron materials. Also the weight of the aluminum alloys is about 30% lower than that of the cast iron.

Advantages of Aluminum Alloy over Cast Iron Material

Based on the hot strength, power losses, light weight and the performance the aluminum alloy pistons are better than the cast iron pistons. Both materials pistons are manufactured using the casting process. The weight of the aluminum alloy is 30% lesser than the cast iron piston. The speeds for aluminum alloys is greater than 6 m/s and for the cast iron piston its less than 6 m/s.

1.    00/01528 EVALUATION OF THERMODYNAMIC PROCESSES IN CARBON FORMATION ON DIESEL ENGINE PISTONS In-text: ('00/01528 Evaluation of thermodynamic processes in carbon formation on diesel engine pistons', 2000) Bibliography: 00/01528 Evaluation of thermodynamic processes in carbon formation on diesel engine pistons. (2000). Fuel And Energy Abstracts, 41(3), 170. doi:10.1016/s0140-6701(00)93258-2

2.    ALIZADEH, A. AND TRIMM, D. L. The formation of deposits from oil under conditions pertinent to diesel engine pistons In-text: (Alizadeh & Trimm, 1985) Bibliography: Alizadeh, A., & Trimm, D. (1985). The formation of deposits from oil under conditions pertinent to diesel engine pistons. Journal Of Chemical Technology And Biotechnology. Chemical Technology, 35(6), 291-296. doi:10.1002/jctb.5040350605


3.    DASHEVSKAYA, G. I. Aluminizing of automobile engine pistons In-text: (Dashevskaya, 1963) Bibliography: Dashevskaya, G. (1963). Aluminizing of automobile engine pistons. Metal Science And Heat Treatment, 5(10), 584-584. doi:10.1007/bf00866158

4.    HOLT, D. J. The diesel engine In-text: (Holt, 2004) Bibliography: Holt, D. (2004). The diesel engine. Warrendale, PA: Society of Automotive Engineers.

5.    JANKOWSKI, A. DESIGN OF NOVEL COMPOSITE PISTONS FOR DIESEL ENGINE In-text: (Jankowski, 2014) Bibliography: Jankowski, A. (2014). DESIGN OF NOVEL COMPOSITE PISTONS FOR DIESEL ENGINE. Journal Of KONES. Powertrain And Transport, 21(4), 211-216. doi:10.5604/12314005.1130473


6.    KAINER, K. U. Metal matrix composites In-text: (Kainer, 2006) Bibliography: Kainer, K. (2006). Metal matrix composites. Weinheim: Wiley-VCH.

7.    KAO, T. AND WALLACE, F. A new approach to the prediction of heat flow and temperature in engine pistons with special reference to thermal barriers In-text: (Kao & Wallace, 1981) Bibliography: Kao, T., & Wallace, F. (1981). A new approach to the prediction of heat flow and temperature in engine pistons with special reference to thermal barriers. International Journal Of Mechanical Sciences, 23(11), 647-659. doi:10.1016/0020-7403(81)90019-9

8.    KOŁOMECKI, J. COMPARATIVE RESEARCHES OF LUBE OIL CONSUMPTIONS ENGINE WOLA S12-U WITH COMPOSITE PISTONS In-text: (KoÅ‚omecki, 2012) Bibliography: KoÅ‚omecki, J. (2012). COMPARATIVE RESEARCHES OF LUBE OIL CONSUMPTIONS ENGINE WOLA S12-U WITH COMPOSITE PISTONS. Journal Of KONES. Powertrain And Transport, 19(4), 315-320. doi:10.5604/12314005.1138466

9.    MANASIJEVIĆ, S., MARKOVIĆ, S., AĆIMOVIĆ - PAVLOVIĆ, Z., RAIĆ, K. AND RADISÌŒA, R. Effect of heat treatment on the microstructure and mechanical properties of piston alloys = In-text: (Manasijević, Marković, Aćimović - Pavlović, Raić & RadisÌŒa, n.d.) Bibliography: Manasijević, S., Marković, S., Aćimović - Pavlović, Z., Raić, K., & RadisÌŒa, R. Effect of heat treatment on the microstructure and mechanical properties of piston alloys =.

10.    MCDEWELL, H. S. Supplementary report of oil scraper piston rings In-text: (McDewell, 1922) Bibliography: McDewell, H. (1922). Supplementary report of oil scraper piston rings. Washington D.C.: National Advisory Committee for Aeronautics.

11.    PIERZ, P. Thermal barrier coating development for diesel engine aluminum pistons In-text: (Pierz, 1993) Bibliography: Pierz, P. (1993). Thermal barrier coating development for diesel engine aluminum pistons. Surface And Coatings Technology, 61(1-3), 60-66. doi:10.1016/0257-8972(93)90203-z

12.    PINSKII, F. I. Temperature measurements of internal-combustion engine pistons In-text: (Pinskii, 1964) Bibliography: Pinskii, F. (1964). Temperature measurements of internal-combustion engine pistons. Measurement Techniques, 7(7), 610-615. doi:10.1007/bf00980044

13.    PRUDNIKOV, A. N. Production, structure, and properties of engine pistons made from transeutectic deformable silumin In-text: (Prudnikov, 2009) Bibliography: Prudnikov, A. (2009). Production, structure, and properties of engine pistons made from transeutectic deformable silumin. Steel Transl., 39(5), 391-393. doi:10.3103/s0967091209050064

14.    SHIOTA, W. Aluminum alloys for engine pistons In-text: (SHIOTA, 1971) Bibliography: SHIOTA, W. (1971). Aluminum alloys for engine pistons. Journal Of Japan Institute Of Light Metals, 21(10), 670-683. doi:10.2464/jilm.21.670

15.    TREFZ, W. The piston and its finishing In-text: (Trefz, n.d.) Bibliography: Trefz, W. The piston and its finishing. Cincinnati, O.: Aluminum industries.

16.    VENKATESH, S. Surface treatments for pistons and their effect on engine performance In-text: (Venkatesh, 1973) Bibliography: Venkatesh, S. (1973). Surface treatments for pistons and their effect on engine performance. Wear, 25(1), 65-71. doi:10.1016/0043-1648(73)90121-x