Documents

Ammcs Using Stir Casting

Description
paper
Categories
Published
of 4
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
Share
Transcript
   Kandpal, et al.,  International Journal of Advanced Engineering Technology E-ISSN 0976-3945    Int J Adv Engg Tech/IV/III/July-Sept.,2013/26-29 Research Paper MANUFACTURING OF AMMCS USING STIR CASTING PROCESS AND TESTING ITS MECHANICAL PROPERTIES Ajay Singh, Love Kumar, Mohit Chaudhary, Om Narayan, PallavSharma, Piyush Singh, *Bhaskar Chandra Kandpal, Som Ashutosh   Address for Correspondence Department of Mechanical Engineering, Inderprastha Engineering College, Ghaziabad, Uttar Pradesh ABSTRACT Aluminum alloys are widely used in aerospace and automobile industries due to their low density and good mechanical  properties, better corrosion resistance and wear, low thermal coefficient of expansion as compared to conventional metals and alloys. The excellent mechanical properties of these materials and relatively low production cost make them a very attractive candidate for a variety of applications both from scientific and technological viewpoints. The aim involved in designing aluminum based metal matrix composite materials is to combine the desirable attributes of metals and Ceramics. Present work is focused on the study of behavior of Aluminum Cast Alloy (6063) with alumina (Al 2 O 3 ) composite produced  by the stir casting technique. Different % age of alumina powder is used as reinforcement phase in this AMMC. Various mechanical tests like tensile test, Hardness Test, Impact test are performed on the samples of AMMC to evaluate the mechanical properties of this aluminum based metal matrix composite. KEYWORDS-  composite, alumina (Al 2 O 3 ), metal matrix composite (MMC), aluminum metal matrix composite (AMMC) 1.   INTRODUCTION The aim involved in designing metal matrix composite materials is to combine the desirable attributes of metals and ceramics. The addition of high strength, high modulus refractory particles to a ductile metal matrix produce a material whose mechanical properties are intermediate between the matrix alloy and the ceramic reinforcement. Aluminium metal matrix composite (AMMCs) refer to the class of light weight high performance aluminium centric material systems. The reinforcement in AMMCs could be in the form of continuous/discontinuous fibres, whisker or  particulates, in volume fractions ranging from a few  percent to 70%. Properties of AMMCs can be tailored to the demands of different industrial applications by suitable combination of matrix, reinforcement and  processing routes. There are various types of AMMCs like Al/SiC, Al/ Al 2 O 3 , Al. TiC, etc. which are commonly used in automotive and defense. These AMMCs have greater demand because of their advanced properties like greater strength, improved stiffness, reduced density, improved high temperature  properties, controlled thermal expansion coefficient, enhanced and tailored electrical properties, improved abrasion and wear resistance, control of mass ,improved damping capabilities. 1.1.   Processing of MMCS Accordingly to the temperature of the metallic   matrix during processing the fabrication of MMCs can be classified into three categories: (a)Liquid phase  processes, (b) solid state processes, and (c) Two  phase (solid-liquid) processes Stir Casting Process -Stir Casting is a liquid state method of composite materials fabrication, in which a dispersed phase (ceramic particles, short fibers) is mixed with a molten matrix metal by means of mechanical stirring. The liquid composite material is then cast by conventional casting methods and may also be processed by conventional Metal forming technologies. The Stir Casting set up is shown in Figure 1. 1.2   Literature review related to MMC and AMMC The main concept of composite is that it contains matrix materials. In composite material the reinforcements can be fibers, particulates or whiskers, and the matrix materials can be metals, plastics, or ceramics. The reinforcements can be made from  polymers, ceramics and metals. [1]. Fig.1- Stir casting (1) Some automotive companies using MMC for disc  brakes also. Honda Company used AMMC for cylinder liners in some of their engines like F20C, F22C and H22A. In recent years considerable development has occurred in nonferrous composites and attention is now being given to make iron based composites. The paper [2] reviews the ongoing research and interaction between iron based materials and reinforcements including wetting and spreading of iron melts on ceramic materials. The paper  provides insight into the evolution of the processes that are used to manufacture iron based composites, and the applications that benefit from their unique characteristics. In order for ferrous based composite materials to find applications in production environments, consistent and controlled mechanical and physical characteristics are required. Ultimately, industry standards need to be written defining the material design parameters. Over the past thirty years Metal Matrix Composites (MMCs) have [3] emerged as an important class of material within the engineering industry. At present, MMCs offer attractive performance or weight-saving alternatives for a wide range of applications within the sport industry, from Formula 1 racing components to golf club shafts. This paper briefly reviews the advantages of MMCs, and presents a study of the effects of additional treatments (heat and surface) which  produce beneficial characteristics in monolithic and alloy materials, but whose effects become more complex when applied to composites. The material used for this study was 2124 Al alloy matrix, reinforced with particulate silicon carbide having a mean particle size of around 3 µm treatment. The influence of machining parameters [4] such as cutting forces and surface roughness on the machinability of LM6/ SiCp metal matrix composites at different weight fraction of SiCp discussed in this paper. It is observed that the depth of cut and the cutting speed at   Kandpal, et al.,  International Journal of Advanced Engineering Technology E-ISSN 0976-3945    Int J Adv Engg Tech/IV/III/July-Sept.,2013/26-29 constant feed rate affects the surface roughness and the cutting forces during dry turning operation of cast MMCs. It is also observed that higher weight  percentage of SiCp reinforcement imparts a higher surface roughness and needs high cutting forces. This experimental analysis and test results on the machinability of Al/SiC-MMC will provide essential guidelines to the manufacturers. A detailed study [5] on the processing of Al-metal matrix composites cites with the reinforcement of different particulates such as SiC, TiN and TiO 2  was carried out. The results of the present studies show that the Al based composites  prepared through various techniques exhibits excellent mechanical, physical and tribological  properties and could emerge as promising materials for defense, aerospace and other engineering applications. With concern [6] increasing over environmental issues, reduction in automobile weight has become more important and has been proved to  be effective for improving fuel efficiency. Metal Matrix Composites (MMC) are expected to be useful to cope with these problems. The authors have developed a new aluminium engine block which has the cylinder bore surface structure reinforced with short hybrid fibres of alumina and carbon. The development of aluminum metal matrix composites (Al-MMC) brake rotor and pad was discussed [7].The improvement in fuel consumption rate requires a reduction in vehicle weight. In this study, we developed aluminum metal matrix composites brake rotor and pads, which have equivalent braking effects and wear resistance to those of the conventional cast iron rotor, by optimization of the quantities and the  particle diameter ratio of hard particles used for the rotor and the pad. Metal matrix composites [8] offer considerable potential for widespread application in most aerospace fields. The potential for the use of these materials in civil aircraft is largely dependent on costs and currently these are too high. However, by the use of appropriate design and manufacturing technology this intrinsic high cost can be overcome to unlock their potential  1.3 Alumina as reinforcement Aluminum oxide, commonly referred to as alumina,  possesses strong ionic inter atomic bonding giving rise to its desirable material characteristics. It can exist in several crystalline phases which all revert to the most stable hexagonal alpha phase at elevated temperatures. Its high hardness, excellent dielectric  properties, refractoriness and good thermal  properties make it the material of choice for a wide range of applications. 1.4 Effect of particle size The deformation and fracture behavior of the composite revealed the importance of particle size. A reduction in particle size is observed to increase the  proportional limit, yield stress and the ultimate tensile stress. It is well established that large particles are detrimental to fracture toughness due to their tendency towards fracture. It would be highly desirable to have a composite system where the reinforcing particles are relatively fine (4µm or less) so as to get the stiffness benefits of a composite without significantly lowering fracture toughness.  1.5 Effect of reinforcement distribution Apart from the reinforcement level, the reinforcement distribution also influences the ductility and fracture toughness of the MMC and hence indirectly the strength. A uniform reinforcement distribution is essential for effective utilization of the load carrying capacity of the reinforcement. Non-uniform distributions of reinforcement in the early stages of processing was observed to persist to the final product in the forms of streaks or clusters of uninfiltrated reinforcement with their attendant porosity, all of which lowered ductility, strength and toughness of the material.  2.   EXPERIENTIAL PROCEDURE 2.1   Preparation of aluminum based metal matrix composite (AMMC) The most important aspects of the microstructure is the distribution of the reinforcing particles, and this depends on the processing and fabrication routes involved. The oxides of reinforcing particles used in the composites have a varying density. Density of the particles is one of the important factors determining the distribution of the particles in molten metal. Particles having higher density than molten metal can settle at the bottom of the bath slowly and particles of lower density can segregate at the top. During subsequent pouring of the composite melt, the particle content may vary from one casting to another or even it can vary in the same casting from one region to another. Therefore uniform distribution of the particles in the melt is a necessary condition for uniform distribution of  particles in the castings. The properties of composites are finally dependent on the distribution of the particles. Hence the study of the distribution of the particles in the composite is of great significance. Aluminum Alloy 6061 was melted in a crucible by heating it in a muffle furnace at 800°C for three to four hours. The Alumina particles were  preheated at 1000 ºC and 900oC respectively for one to three hours to make their surfaces oxidized. The furnace temperature was first raised above the liquidus temperature of Aluminum near about 750 ºC to melt the Al alloy completely and was then cooled down just below the liquidus to keep the slurry in Semi solid state. Automatic stirring was carried out with the help of radial drilling machine for about 10 minutes at stirring rate of 290 RPM. At this stage, the preheated Alumina particles were added manually to the vortex. In the final mixing processes the furnace temperature was controlled within 700 ± 10ºC. After stirring process the mixture was pour in the other mould to get desired shape of specimen as shown in Figure. The presence of reinforcement throughout the specimen was inspected by cutting the casting at different locations and under microscopic examination. Same process was used for specimens with different compositions of Alumina. Compositions of samples are shown in Table 1: Table 1- Compositions of samples S. No Sample composition (%of alumina in ammc) Aluminium alloy 6063 ( grams) Aluminium oxide ( grams) 1 2.5 1950 50 2 5 1900 100 3 7.5 1850 150 4 10 1800 200   Kandpal, et al.,  Interna  Int J Adv Engg Tech/IV/III/July-Sept.,2013/2 2.2 Preparation of Patterns design a In this step we have prepared patters various mechanical tests. Fig.2 -Pattern Drawing of various test Fig 3- Torsion pattern Fig 4 -Fat atter Fig 5- Tensile pattern 2.3 Mould Making Process In this step we have prepared moul specimen of various mechanical tests test, hardness test, torsion test, etc. Fig 6- Mould Making 2.4 Casting Process In this step   we have first prepared alu composite material in the open hear discussed in above section to cast various mechanical tests.   ional Journal of Advanced Engineering Technology 6-29 d pattern of wood for specimens gue for casting like tensile minum based h furnace as   specimens of Fig 7- Casting 2.5 Casted samples of aluminu matrix composite   Fig8 - Sample of impact Fig9 - Sample of fatigue 2.6 Mechanical testing of casted A After casting samples of various me AMMC material, following mech carried out to check the check  properties of composite material. done on various mechanical testin universal testing machine, Vickers machine, impact testing machine as section.  2.6.1  Impact Test    The Charpy impact test, also know V-notch test, is a standardized highwhich determines the amount of enea material during fracture. This abso measure of a given material's toughn Fig.10 – Impact testing mach With the increase in Al 2 O 3  con strength is increases w.r.t. base met  proper dispersion of Al 2 O 3  into the interfacial bonding in between the Alumina interfaces. 2.6.2  Hardness test    A Vicker hardness tester machin hardness measurement of composite Fig 11. – Vickers testing -ISSN 0976-3945   m based metal test test MC chanical test of nical tests are he mechanical hese tests are machines like ardness testing iscussed in this as the Charpy strain- rate test rgy absorbed by rbed energy is a ess. ine (10)   stituent Impact l. This is due to matrix or strong Al alloy 6063& e used for the material. (10)   Kandpal, et al.,  International Journal of Advanced Engineering Technology E-ISSN 0976-3945    Int J Adv Engg Tech/IV/III/July-Sept.,2013/26-29 The results predict that uniform increase in hardness is also seen. This is due to increase in resistance to deformation by adding Alumina as reinforcement in 6063 alloy. 2.6.3 Tensile test    Tensile tests were used to assess the mechanical  behavior of the composites and matrix alloy. The composite and matrix alloy rods were machined to tensile specimens with a diameter of 6mm and gauge length of 30 mm. As the reinforcement wt. % increases, UTS is also increases. This happens may  be due to dispersion of Alumina which creates hindrance to dislocation motion. This may results increase in tensile strength of reinforced Al 6063 alloy. All these mechanical tests are done properly as per the standards given in various material testing books. For these tests we observed improved in mechanical  properties of newly manufactured AMMC material using stir casting as compared to aluminum alloy 6063 and aluminum oxide. Figure12 – Universal testing machine (10) CONCLUSION  The conclusions drawn from the present investigation are as follows: ã   The results confirmed that stir formed Al alloy 6063 with Al 2 O 3  reinforced composites is clearly superior to base Al alloy 6063 in the comparison of tensile strength, Impact strength as well as Hardness. ã   Dispersion of Al 2 O 3  particles in aluminum matrix improves the hardness of the matrix material. ã   It is found that elongation tends to decrease with increasing particles wt. percentage, which confirms that alumina addition increases  brittleness. ã   Aluminum matrix composites have been successfully fabricated by stir casting technique with fairly uniform distribution of Al 2 O 3  particles. ã   It appears from this study that UTS and Yield strength trend starts increases with increase in weight percentage of Al 2 O 3  in the matrix. ACKNOWLEDGEMENTS The authors would like to acknowledge the support of, in particularly Department of Mechanical Engineering, Inderprastha Engineering College, Ghaziabad, U.P funding the current research in this area. REFERENCES 1.   J. Hashim, L. Looney, M.S.J. Hashmi , “Particle distribution in cast metal matrix composites—Part I” Journal of Materials Processing Technology, Volume 123, Issue 2, 30 April 2002, pp: 251–257 2.   Sanjay K. Mazumdar, “Composites manufacturing”, CRC Press, 2010. 3.   R. M. Hathaway, P.K. Rohatgi, N. Sobczak, J. Sobczak, “Ferrous composites: A review” , oshkosh truck corporation, oshkosh, wisconsin, University of Wisconsin –Milwaukee, Milwaukee, Wisconsin, USA, Foundry research institute, Cracow, Poland. 4.   D. Bacon, J. Moffatt, L. Edwards and M.E. Fitzpatrick, “Metal Matrix Composites: In the driving seat”, Dept of Materials Engineering, The Open University, Walton Hall, Milton Keynes MK7 6AA A. D. Tarrant Aerospace Metal Composites Limited, REA Road, Farnborough, Hampshire GU14 6XE 5.   Rabindra Behera, S. Kayal, N.R. Mohanta, G. Sutradharda, “Study on machinability of Aluminium Silicon Carbide Metal Matrix Composites”, Journal of Minerals & Materials Characterization & Engineering, Vol. 10, No.10, pp.923-939, 2011. 6.   K. Venkateswarlu , A. K. Ray, S. K. Chaudhury and L. C. Pathak, “Development of aluminium based metal matrix composites”, National metallurgical laboratory, Jamshedpur - 831007, India. 7.   Shimotakanezawa, Haga-Machi, Haga-Gun, “Tribological application of MMC for reducing engine weight”, Kazuo Shibata, Hideaki Ushio, Tribology International, Volume 27, Issue 1, February 1994, pp: 39–44 . 8.   Hiroaki Nakanishi, Kenji, Akinori, etc., “Development of aluminum metal matrix composites (Al-MMC) brake rotor and pad” , JSAE Review , Volume 23, Issue 3, July 2002, pp: 365–370. 9.   David Charles , “Unlocking the potential of metal matrix composites for civil aircraft”,Materials Science and Engineering: A Review, Volume 135, European Materials Research Society 1990 Spring Meeting on Metal Matrix Composites, 30 March 1991, pp: 295– 297. 10.   http://www.araifid.com/testing_validation_metallurgical_testing.asp  

Safdar Jang

Jul 23, 2017

Acts Book

Jul 23, 2017
Search
Tags
Related Search
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks