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1、Unit7MaterialsScienceWhatismaterials?StuffIngeneralanythingmadeofmattermorenarrowlysubstancesorcomponentswithcertainphysicalpropertiesthatareusedasinputstoproductionormanufacturing.naturalstuffwoodbonestrawwoolcottonsilkstoneWhatmaterialsdoyouknow?syntheticstuffsteelpotte
2、ryplasticsemiconductorsconcretetextilespapergeneralcategoriescomposite['kɔmpəzit]复合材料semiconductormetalpolymer聚合物/高分子化合物biomaterialceramic[si'ræmik]陶瓷PropertiesandapplicationsofmaterialsMaterialsPropertiesApplicationscompositesemiconductormetalpolymerbiomaterialceramicTas
3、k1:Matchthepictureswiththerighttypes.(B)1.Composite.Compositesareusedbecauseoverallpropertiesofthecompositesaresuperiortothoseoftheindividualcomponents.Manyracketswhichareusedinsportssuchastennisandbadmintonareallmadeofcomposites.(E)2.Semiconductor."Semiconductor"meansama
4、terialcanconductelectricitywithabitofhelpintheformofadded"impurities."YourCD,DVDplayer,telephoneandradioalldependonsemiconductors(A)3.Metal.Itisakindofmaterialwithobviouspropertyofconductingheatandelectricity.Themostcommontypesofmetalsincludesteel,iron,copper,aluminumands
5、oon.(C)4.Polymer.Itisakindofmaterialwiththepropertyoflightweightandpoorconductingofelectricityandheat.Plastic,paintandrubberareallmadeofpolymer.(F)5.Biomaterials.Scientiststrytomimicnature'sdesignstocreatematerialsforotheruses,suchasusingthefoamstructureofboneasaninspirat
6、ionfordesigningmaterialsthatarelightweightandstrong.(D)6.Ceramic.Examplesofsuchmaterialscanbeanythingsuchasclay.Someoftheusefulpropertiesofceramicsincludehighmeltingtemperature,lowdensity,highstrength,hardness,andcorrosionresistance.Manyceramicsaregoodelectricalandthermal
7、insulators.MaterialsPropertiesApplicationscompositesuperiortoindividualsemiconductorconductivitybetweenconductorsandnonconductorsorinsulatorsmetalhard,strongconductorpolymerlightweight,insulator,cheaper,easiertoformintoshapesbiomateriallightweight,strongceramichard,strong
8、,insulatorhighmeltingpointcorrosionresistanceSomenewmaterialsTask2:1.Matchthenewswiththerighthea