International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395 -0056 Volume: 02 Issue: 04 | July-2015 www.irjet.netp-ISSN: 2395-0072 2015, IRJET.NET- All Rights Reserved Page 1326 Effect of Silicon content on the Mechanical Properties of Aluminum Alloy Vipin Kumar1, Husain Mehdi2 Arpit Kumar1 1, M.Tech Student, Department of Mechanical Engineering, NITTTR, Chandigarh, India 2Department of Mechanical Engineering, Meerut Institute of Technology, Meerut, India ---------------------------------------------------------------------***---------------------------------------------------------------------Abstract-Aluminiumalloysarewidelyusedin automotiveindustries.Thisisparticularlyduetothe realneedtoweightsavingformorereductionoffuel consumption.Thetypicalalloyingelementsare copper,magnesium,manganese,silicon,andzinc. Surfacesofaluminiumalloyshaveabrilliantlustrein dryenvironmentduetotheformationofashielding layerofaluminiumoxide.Aluminiumalloysofthe 4xxx,5xxxand6xxxseries,containingmajor elementaladditivesofMgandSi,arenowbeingused toreplacesteelpanelsinvariousautomobile industries.Inthisworkweareinterestedto investigatethemechanicalpropertiesofaluminium alloybyvaryingthepercentageofsilicon.Theresults showedthatwiththeincreasingofsiliconcontentthe solidificationtimeincreased,asalsoadecreasingthe liquidstemperature.Thetensilestrengthof aluminiumalloyisincreasedwithincreasedsilicon content up to 6 %. KeyWords:Silicon,Aluminium,AluminiumAlloy, Ultimate Strength 1. Introduction Analloyisamaterialthathasmetallicpropertiesandis formed by combination of two ormore chemical elements ofwhichatleastoneisametal.Themetallicatomsmust dominateinitschemicalcompositionandthemetallic bondinitscrystalstructure.Commonly,alloyshave differentpropertiesfromthoseofthecomponent elements. An alloy of a metal is made by combining it with oneormoreothermetalsornon-metalsthatoften enhancesitsproperties.Forexample,steelisstronger thanironwhichitsprimaryelement.Thephysical properties,suchasdensityandconductivity,ofanalloy maynotdiffergreatlyfromthoseofitscomponent elements,butengineeringpropertiessuchastensile strength and shear strength may be considerably different from those of the constituent materials[1] ThetribologicalpropertiesofAl-Sialloysareaffectedby shapeanddistributionof siliconparticles,andadditionof alloyingelementssuchascopper,magnesium,nickel,and zincoftencombinedwithasuitableheattreatment[1-3]. TheexcellenttribologicalpropertiesAl-Sialloyshaveled totheirextensiveusesinengineeringapplication, particularlyinplainbearings,internalcombustionengine pistons,andcylinderliners[4,5].Siliconispresentasa uniformlydistributedfineparticleinthestructure. However,whentheprimarysiliconappearsascoarse polyhedral particles, the strength properties decrease with increasingsiliconcontent,butthehardnessgoeson increasing because of the increase in the number of silicon particles[6].Thehigh-temperaturecreepresistanceof magnesium alloys was discussed, with special reference to Mg-AlandMg-Yalloys.Mg-Alsolid-solutionalloysare superiortoAl-Mgsolid-solutionalloysintermsofcreep resistance.Thisisattributedtothehighinternalstress typicalofanHCPstructurehavingonlytwoindependent basalslipsystems[7].Manganeseisalsoabletochange the morphology of the iron-rich phases from platelets to a morecubicformortoglobules.Thesemorphologies improvetensilestrength,elongation,andductility[8,9].If theironcontentexceeds0.45wt.%,itisreportedthatthe manganese content should not be less than half of the iron [10].Aluminiumalloyswithsiliconasamajoralloying elementareaclassofalloys,whicharethebasisofmany manufacturedcastings.Thisismainlyduetothe outstanding effect of silicon in the improvement of casting characteristics,combinedwithotherphysicalproperties, suchasmechanicalpropertiesandcorrosionresistance [11].Siliconisnotonlythemostfrequentimpurityin commercialpurealuminium,butalsothemostcommon alloyingelement[12].TheinfluenceoftheSicontentof thealuminiumalloysontheirwearresistancehasbeen welldocumentedandeutecticalloysarereportedtohave betterwearresistancethanthoseofhypoeutecticand hypereutecticcomposition[13].Forgedwheelshavebeen usedwheretheloadingconditionsaremoreextremeand wherehighermechanicalpropertiesarerequired. Aluminium alloys have also found extensive application in heatexchangers.Modern,highperformanceautomobiles havemanyindividualheatexchangers,e.g.engineand transmissioncooling,chargeaircoolers(CACs),climate control, made up of aluminium alloys [14]. International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395 -0056 Volume: 02 Issue: 04 | July-2015 www.irjet.netp-ISSN: 2395-0072 2015, IRJET.NET- All Rights Reserved Page 1327 Theseveralmethodsforestimatingfatiguepropertiesof wroughtaluminiumalloysfromsimpletensiledataor hardness was discussed. Among them, Park-Song modified Mitchellsmethodprovidedthebestestimationresultsin low fatigue life regime [15].TheretrogressionheattreatmentisperformedonAlloy AA7075-T6atvarioustemperaturesandholdtimes,and subsequentagingisperformedat130Cfor12h.The microstructureandmechanicalpropertiesof thealloyare studieddependingonthetemperatureandtheholdtime oftheretrogressionheattreatment.Electronmicroscopic studiesarepreformedandmechanicalcharacteristicsare determined in tensile and impact tests [16] Inthisworkweinvestigatethemechanicalpropertiesof aluminiumalloytovarythepercentageofsilicon,using specimenspreparedwithreferencetoASTMD638-02a [17]. 2.Experimental Procedure: Inthisprocess,themetalwhichhashighestmelting temperature is firstly poured in the crucible and allowed to meltonthefurnace.Themetalwhichposseslowmelting temperatureisallowedtomeltinthelastbecauseif itwill allowedtomeltwithmetalwhichposseshighest temperaturethenlowestmeltingtemperaturemetalwill get burn (a) (b) (c) Figure 1: (a) Pouring of molten metal into mould cavity, (b) Unfinished Product, (c) Finished Product Afterpouringmoltenmetalinthemouldcavityallows solidifying into the mould cavity. The solidification time of the molten metal is given by Kornichovs Criterion. According the Kornichovs criterion, the solidification time ofthemoltenmetalinthemouldcavityisdirectly proportionaltothesquareoftheratioofvolumetothe surface area of the cavity.Ts [v/S.A] 2(1) Ts = k [v/S.A] 2(2) Ts= Solidification Time k = Constant of proportionality V = Volume of the cavity S.A. = Surface area of the mould cavity International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395 -0056 Volume: 02 Issue: 04 | July-2015 www.irjet.netp-ISSN: 2395-0072 2015, IRJET.NET- All Rights Reserved Page 1328 Table 1:- Dimensions of Test Specimen Dimension (mm) Thickness 7mm or less over 7 to 14 mm Type-I Type-II Type-III W- Width 13619 L-Length575757 WO-Width over all191929 LO Length over all165183246 G-Gage length505050 D- grips Distance115135115 Figure 2:- Drawing of Test Specimen Thespecimens1and,2aremadewiththehelpofASTM code D638-02 a [21] and have the characteristics.Specimen 1 made of Type-I Specimen 2 made of Type-II Table 2:- Composition of Aluminium Alloy Alloyingcomponents Al-Alloy Si-1.5% Al-Alloy Si-3% Al-Alloy Si-4.5% Al-Alloy Si-6% Silicon 1.534.56 Aluminium 92.991.489.988.4 Copper 3333 Iron 0.80.80.80.8 Manganese 0.40.40.40.4 Nickel0.30.30.30.3 Zinc 0.50.50.50.5 Lead 0.10.10.10.1 Tin 0.10.10.10.1 Titanium0.20.20.20.2 Magnesium0.20.20.20.2 3.Result and Discussions: Siliconisthemostimportantsinglealloyingelementused inmajorityofaluminumcastingalloys.Itisprimarily responsibleforhighfluidity,lowshrinkage,lowdensity whichmaybeadvantageinreducingtotalweightofcast componentandhasverylowsolubilityinAluminum thereforeprecipitatesasvirtuallypureSiwhichishard andimprovetheabrasionresistance.Sireducesthermal expansion coefficient of Al-Si alloys MaterialSpecimen Ultimate TensileStrength (N/mm2) Mean Ultimate Tensile Strength (N/mm2) Al-Alloy(1.5 % Si) 1119.21 120.87 2122.54 Al-Alloy(3.0 % Si) 1129.12 130.88 2132.65 Al-Alloy(4.5 % Si) 1138.24 139.74 2141.25 Al-Alloy(6.0 % Si) 1148.74 148.99 2149.25 (a) (b) International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395 -0056 Volume: 02 Issue: 04 | July-2015 www.irjet.netp-ISSN: 2395-0072 2015, IRJET.NET- All Rights Reserved Page 1329 (c) (d) Figure 3:- Stress Strain Diagram for Aluminium Alloy (a) Si-1.5%, (b) Si-3%, (c) Si-4.5%, (d) Si-6% Thestress-straincurveforAluminiumspecimenswithan enlargedscale,nowshowingstrainsfromzeroupto specimenfracture.Hereitappearsthattherateofstrain hardeningdiminishesuptoUTS(UltimateTensile Strength).Beyond that point, the material appears to strain soften, so that each increment of additional strain requires a smaller stress. A Study on Mechanical Propertiesof Aluminium Alloy with variationofSiliconelement,tensiletestiscarriedoutat room temperature using universal testing machine. The variation of the silicon particles in aluminium alloy as shownintable-2.Itcanbeseenthattheultimatetensile strengthofaluminiumalloyisincreasedwithincreasein siliconcontentasshownintable3.Thedensityofthe alloysdecreasedasthesiliconcontentincreased.The maximumtensilestrengthwasfoundinAluminiumalloy (6%of silicon)148.99MPa,whenwedecreasethesilicon contentthenthetensilestrengthwillbedecreases,the minimumtensilestrengthwasfoundinAluminiumalloy (1.5% of silicon) 120.87 MPa. Conclusion:The mechanical properties of aluminium alloy was calculated with variation of silicon content, the following conclusion are as followed. When we increase the silicon content then the melting point of aluminium alloy is decreases whereas fluidity will increases. The ultimate tensile strength will increases when we increase the silicon content. The Maximum ultimate tensile strength was 148.99 MPa in 6% of silicon content in aluminium alloy. The Minimum ultimate tensile strength was 120.87 MPa in 1.5% of silicon content in aluminium alloy. REFERENCES [1]Yang C.Y., Lee S.L., Lee G.K., Lin J.G., Effect of Sr and Sb modifiersontheslidingbehaviourofA357alloy undervaryingpressureandspeedconditions,Wear, 2006, 261, p. 1348-1358.[2] HarunM.,TalibI.A.,DaudA.R.,Effectofelement additionsonwearpropertyofeutecticaluminium-Silicon alloys, Wear, 1996, 194, p.54-59.[3]DwivediD.K.,Wearbehaviourofcasthypereutectic aluminiumsiliconalloys,MaterDes.,2006,27(7),p. 610-616. [4]DavisF.A.,EyreT.S.,Theeffectofsiliconcontentand morphologyonthewearofaluminium-siliconalloys underdryandlubricatedslidingconditions, Tribology International, 1994, 27(1), p. 171-181.[5]TorabianH.,PathakJ.P.,TiwariS.N.,Onwear characteristicsofleadedaluminiumsiliconalloys,Wear,1994, 177(1), p.47-54. [6]TorabianH.,PathakJ.P.,TiwariS.N.,Wear CharacteristicsofAl-SiAlloys,Wear,1994,172(1),p. 49-58. [7]KouichiMaruyama,MayumiSuzuki,andHiroyuki Sato,Creepstrengthofmagnesium-basedalloys,vol. 42, 2008. [8]S.G.Shabestari,M.Mahmudi,M.Emami,J.Campbell, Inter. J. Cast Metals Res. 15 (2002) 724.[9]J.L.Jorstad,DieCastingEng.,November/December 1986.[10] A.Couture,AFSInter.CastMetalsJ.6(4)(1981)917. [11] E.L.Rooy,MetalsHandbook,Vol.15,ASM International, Materials Park, Ohio, 1988, p743- 770. [12] M.Johnsson:Z.Metallkd.InfluenceofZrongrain refinement of aluminium, 85 (1994) 781-785. [13] SinghM.,PrasadB.K.,MondalD.P.,JhaA.K.,Dry sliding wear behaviour of an aluminium alloy-granite particlecomposite,TribologyInternational,2001, 34(8), p. 557-567. International Research Journal of Engineering and Technology (IRJET)e-ISSN: 2395 -0056 Volume: 02 Issue: 04 | July-2015 www.irjet.netp-ISSN: 2395-0072 2015, IRJET.NET- All Rights Reserved Page 1330 [14]MillerW.S.,ZhuangL.,Recentdevelopmentin aluminiumalloysfortheautomotiveindustry, MaterialsScienceandEngineering:A,Volume280, Issue 1, Pages 37-49 [15] Jing li, Zhong-ping zhang, Qing sun, Chun-Wang li, and Rong-suiliamodifiedmethodtoestimatefatigue parametersofwroughtaluminiumalloys,july31, 2010).[16] A.KaraKaraaslan,I.KayaandH.Atapek,Effectof agingtemperatureandofretrogressiontreatment timeonthemicrostructureandmechanical propertiesofalloy7075,MetalScienceandHeat Treatment Vol. 49, Nos. 9 10, 2007. [17] Mehdi.HetalExperimentalAnalysisofMechanical PropertiesofCompositeMaterialReinforcedby Aluminium-SyntheticFibersInternationaljournalof MechanicalEngineering,vol-2,issue-2,pp-59-69, 2014. [18] N. Fridlyander,1 O. E. Grushko,1 and L. M. Sheveleva1, Heathardenedalloyv1341forcoldpressingof sheets, Vol. 46, Nos. 9 10, 2004. [19]M.Elmadagli,A.T.Alpas:SlidingwearofanAl-18.5wt. % Si alloy tested in an argon atmosphere and againstDLCcoatedcounterfaces,Wear261(7-8) (2006), pp. 823-834. [20] Mehdi.HetalModalAnalysisofCompositeBeam ReinforcedbyAluminium-SyntheticFiberswithand withoutMultipleCracksUsingANSYSInternational journalofMechanicalEngineering,vol-4issue-2,pp 70-80, 2014 [21] ThejurisdictionofASTMCommitteeD20onPlastics andisthedirectresponsibilityofSubcommittee D20.10onMechanicalProperties.Currentedition approved November 10, 2002. [22] KouichiMaruyama,MayumiSuzuki,andHiroyuki Sato,Creepstrengthofmagnesium-basedalloys,vol. 42, 2008. [23] Das,S.,Mondal,D.P.,Sawla,S.&Ramakrishnan, N.(2008).Synergiceffectofreinforcementandheat treatmentonthetwobodyabrasivewearofanAl-Si alloyundervaryingloadsandabrasivesizes.Wear. Volume264, Issues 1-2. Pages 47-59. BIOGRAPHIES Corrospondingauthor,Vipin KumardoingM.Tech (ManufacturingTechnology) fromNITTTR,Chandigarh IndiaintheDepartmentof MechanicalEngineering.His coreareaofinterestis ManufacturingTechnology, MaterialScienceandmany more. ArpitKumardoingM.Tech (ManufacturingTechnology) fromNITTTR,Chandigarh IndiaintheDepartmentof MechanicalEngineering.His coreareaofinterestis ManufacturingTechnology, Material Science. HusainMehdihavedonehis M.Tech(MachineDesign)from AligarhMuslimUniversity, Aligarh, (U.P), India. Now he is anAssistantProfessorinthe DepartmentofMechanical Engineeringtowardsthe growthofprofessionally managedorganizationMeerut InstituteofTechnology, Meerut,past3years.Hiscore areaofinterestisMachine design,andiscontinuously performingresearchworkon CompositeMaterial,Material Scienceandcomputational fluidDynamicsandmany more