Characteristics
Itscharacteristicsintermsofmechanicsarehightransverseandshearstrength,goodcomprehensivemechanicalpropertiessuchastoughnessandfatigue,aswellasthermalconductivity,electricalconductivity,wearresistance,andthermalexpansioncoefficient.Ithastheadvantagesofsmallsize,gooddamping,nomoistureabsorption,noagingandnopollution.Forexample,carbonfiberreinforcedaluminumcompositematerialshaveaspecificstrengthof3to4×107mmandaspecificmodulusof6to8×109mm.Forexample,graphitefiberreinforcedmagnesiumnotonlyhasaspecificmodulusof1.5×1010mm,butalsohasathermalexpansioncoefficientclosetozero.
Classification
Metalmatrixcompositematerialsareclassifiedaccordingtothetypesofreinforcements,suchasfiberreinforcement(includingcontinuousandshortcut),whiskerreinforcementandparticlereinforcement,etc.,accordingtometaloralloyThematrixisdifferent,metalmatrixcompositematerialscanbedividedintoaluminum-based,magnesium-based,copper-based,titanium-based,high-temperaturealloy-based,intermetalliccompound-basedandrefractorymetal-basedcompositematerials.Duetothehighprocessingtemperature,complexprocess,difficultinterfacereactioncontrol,andrelativelyhighcostofsuchcompositematerials,theapplicationmaturityisfarlessthanthatofresin-basedcompositematerials,andtheapplicationrangeisrelativelysmall.
Application
Resinmatrixcompositescanusuallyonlybeusedindifferenttemperaturerangesbelow350℃.Inrecentyears,variousmetalmatrixcompositematerialssuitableforuseat350°Cto1200°Carebeingrapidlydevelopedandresearched.Metalmatrixcompositematerialisacompositematerialmadebycombiningmetaloralloyasthematrixwithvariousreinforcingmaterials.Thereinforcingmaterialcanbesiliconcarbide,boron,aluminumoxide,andcarbonfiberintheformoffibers,particles,andwhiskers.Inadditiontometalsubstratessuchasaluminumandmagnesium,non-ferrousmetalssuchastitanium,copper,zinc,lead,berylliumsuperalloys,intermetalliccompounds,andferrousmetalshavealsobeendevelopedasmetalsubstrates.Metalmatrixcompositeshavethesamehighstrengthandhighmodulusasresinmatrixcomposites.Theycanwithstandhightemperatures,arenon-flammable,non-moisture-absorbing,havegoodthermalandelectricalconductivity,andareresistanttoradiation.Itisaneye-catchinghigh-temperaturematerialforaerospaceandcanbeusedasasurfacematerialforaircraftturbineenginesandrocketenginehotzonesandsupersonicaircraft.Thecontinuousdevelopmentandimprovementofmetalmatrixcompositematerialsisthefastestgrowingsiliconcarbideparticlealuminumalloy.Thespecificgravityofthismetalmatrixcompositeisonly1/3ofsteeland2/3oftitaniumalloy,whichissimilartoaluminumalloy.Itsstrengthisbetterthanmediumcarbonsteel,similartotitaniumalloybutslightlyhigherthanaluminumalloy.Itswearresistanceisalsobetterthantitaniumalloyandaluminumalloy.Ithasbeenappliedinsmallbatchesintheautomobileindustryandmachineryindustry.Thecommercialapplicationprospectsin5-15yearsareautomobilepistons,brakeparts,connectingrods,robotparts,computerparts,sportsequipment,etc.
Problems
Themainproblemofmetalmatrixcompositesisthatthemanufacturingprocessofmetalcompositesiscomplexandexpensive,andtheyhavenotyetbeenappliedinindustrial-scaleproduction.
Researchprogress
In2015,Americanscientistsdevelopedabrand-newmetalmaterialthatcanfloatonwater.Thisnewlight-weightmaterialiscalled"metalmatrixcompositematerial"andisjointlydevelopedbytheUSmilitaryandscientiststohelpwarshipsavoidsinkingunderstructuraldamage.