CMBYkTI4

4-1

44 ssmm<< ½½nn§§eellaahh³³

(Metallic Bonding) sm<½n§enAkñúgelah³RtUv)anBnül;)any:agRbesIrbMputedayRTwsþIGrb‘Ítallm:UelKul EdleyIg)anBiPakSarYcral;ehIyenAkñúgGtßbTsm<½n§kUv:aLg;. karerobcMGatUmenAkñúgRKIsþal; elah³GacRtUv)anbkRsaycMeBaHkarpÁúMCiténEsV‘d¾rwg. karpÁúMCitenHKWmanlkçN³TUeTAcMeBaH TaMgsmasFatuelah³ nigsmasFatuGuIy:ug. dUecñH karsikSaBIsm<½n§elah³pþl;[nUvTMnak; TMngrvagsm<½n§kUv:aLg; nigsm<½n§GuIy:ug. eyabkelah³BIEr: KWRsbeBlCamYynwgPaBrIkcMerIn. sMriT§ (bronze) CasMelah³rvag Tg;EdgnigsMN):ahaMg KWCaelah³dMbUgEdlRtUv)aneKeRbIR)as;y:agTUlMTUlay. edaysarEt bec©keTsrMlaykan;EtmankarrIkcMerIn Edk)ankøayCaelah³EdleKniym eRBaHvamanlkçN³ rwg nigskþismCagsMriT§kñúgkarplitCadav nigngÁ½l. sRmab;kareRbIR)as;CaeRKOglm¥ mas nigR)ak;manPaBgayRsYlkñúgkareRbIR)as; eRBaHvaCaelah³EdlGacEp b¤kinCasnøwk)an ¬KWfa vaGaceFVI[ecjCarUbragepSg²)any:aggay¦. CaeRcInstvtSmkehIy cMnYnelah³EdleK)ansÁal;mankarekIneLIgrhUtdl;cMnYnd¾ eRcIndUceBlsBVéf¶ vaKwCaFatuKImIEdlmancMnYneRcInelIslubenAkñúgtaragxYbKImI. b:uEnþenAkñúg BiPBelakshsm½yenH vaenAEtCacMnYnd¾ticénelah³EdlRtUvkarkñúgCIvitrs;enArbs;eyIg CaBiess KWEdk Tg;Edg GaluymIj:Úm nigs½gásI. elah³EdleyIgeRCIserIs RtUvEtsmeTA nwgeKalbMngEdleyIgRtUvkarva b:uEnþPaBEdlGacrk)anénEr: k¾dUcCatémøéneyabkCajwkjy Caehtuplcm,gEdl[eKeRCIserIselah³mYy CaCagelah³mYyeTot. 4/1 sm<½n§elah³ enAkñúgkarBiPakSarbs;eyIgeTAelIcMEnkfñak;Fatu ¬emIlemeronTI2¦ eyIg)aneFVIkar KUsbBa¢ak;fa karcmøgcrnþGKÁisnIvimaRtbIx<s;enA SATP KWCalkçN³BiessmYyénsm<½n§ elah³. eyIgGaceFVIkarTak;TglkçN³enHeTAnwgsm<½n§enAkñúgelah³. mindUcCaGelah³eT EdlkarEckcayeGLicRtugPaKeRcInenAkñúgÉktam:UelKuldac;²BIKñaenaH GatUmelah³Eck

sm<½n§elah³

4-2

cayeGLicRtugxageRkA ¬eGLicRtugv:aLg;¦ CamYynwgGatUmCitxagEdlCitbMput. vaKWCa bmøas;TIesrIéneGLicRtugBaseBjTRmg;elah³ EdlGacRtUv)aneKeRbIedIm,IBnül;BIPaBcmøg kemþAnigGKÁisnIx<s;énelah³ k¾dUcCaPaBcmñaMgpøatd¾x<s;rbs;va. kgVHxatTisedAénsm<½n§GacRtUv)aneRbIedIm,IBnül;BIPaBEdlGacEp nighUtCalYs)an énelah³PaKeRcIn KWfaGatUmelah³GacrGilelIKñaedIm,IbegáItTRmg;sm<½n§elah³fμI. kar begáItsm<½n§elah³Bnül;BIlT§PaBrbs;eyIgkñúgkarbegáItTRmg;elah³rwg edaykarcak;bMeBj Bum<CamYynwgemSAelah³ nigdak;emSAenHeRkamlkçxNÐsItuNðPaBnigsm<aFx<s;. enAeRkam lkçxNÐenHsm<½n§elah³-elah³RtUv)anbegáItkat;tamRBMEdnRKab;emSA edayKμaneFVI[RKab; elah³TaMgGs;rlay. dMeNIrkarenHeKehAfa rlayesI (sinter). xN³eBlEdlm:UelKulkUv:aLg;samBaØCaTUeTAmancMNucrlayTab ehIysmasFatu GuIy:ugmancMNucrlayx<s; elah³mancMNucrlaycenøaHBI -39ºC sRmab;)art eTA +3410ºC

sRmab;tg;Esþn. elah³bnþcmøgkemþA nigcrnþGKÁisnIenAkñúgPaBrlayrbs;va. ¬tamkarBit elah³Gal;kaLaMgrlay CajwkjyRtUv)aneKeRbICaPñak;garbenÞrkemþAenAkñúgfamBlnuyekø EG‘¦. enHKWCaPsþútagEdlsm<½n§elah³RtUv)anrkSaenAkñúgpasrav. vaKWcMNucrMBuHEdlTak;TgCitsñiT§bMputeTAnwgkmøaMgsm<½n§elah³. ]TahrN_ )artman cMNucrMBuH 357ºC ehIyGg;tal;BIGatUmkmμ 61 kJ.mol-1 ehIytg;EsþnmancMNucrMBuH 5660ºC ehIymanGg;tal;BIGatUmkmμ 837 kJ.mol-1. dUecñH sm<½n§elah³enAkñúg)artKWexSaydUc kmøaMgGnþrm:UelKulxøHEdr cMEnkÉkmøaMgsm<½n§enAkñúgtg;EsþnGaceRbobeFob)aneTAnwgkmøaMg énsm<½n§kUv:aLg;eRcIn. eTaHbICay:agNak¾eday enAkñúgpas]sμ ½nFatuelah³dUcCalIcUmman enACaKU Li2 b¤k¾dUcCaebrüÚm EdlenACaGatUmEtÉg ehIydUecñH)at;bg;nUvlkçN³elah³rbs; va. elah³enAkñúgpas]sμ ½nemIleTAmindUcCaelah³pgeT ]TahrN_ enAkñúgpas]s μ½n b:Uta süÚmmanBN’ébtg. 4/2 KMrUsm<½n§ RTwsþIsm<½n§elah³Nak¾eday RtUvEtmankarBnül;BIlkçN³sMxan;énelah³ ehIy lkçN³sMxan;bMputenaHKWPaBcmøgcrnþGKÁisnIx<s;rbs;elah³¬emIlCMBYkTI2¦. elIsBIenH eTot KMrUNak¾eday KYrEtmankarBnül;BIPaBcmøgkemþA nigPaBcmñaMgpøatx<s;énelah³ ¬PøWrelagelah³ [metallic luster]¦.

CMBYkTI4

4-3

KMrUsm<½n§elah³samBaØbMput KW KMrUsmuRT-eGLicRtug ¬b¤k¾eGLicRtug-]sμ ½n¦. enAkñúg KMrUenH eGLicRtugv:aLg;Gacpøas;TIedayesrIkat;tamTRmg;elah³ ¬ehtuenHeTIbeRbIBakü smuRTeGLicRtug¦ ehIyebIeTaHbICaecjBIelah³begáItnUvGuIy:ugviC¢mank¾eday. vaKweGLic Rtugv:aLg;EdlbegáIt[mancrnþGKÁisnI ehIyvaKwCaclnaéneGLicRtugv;aLg;EdlepÞrkemþAkat; tamelah³. eTaHbICay:agNak¾eday KMrUenH KWmanlkçN³CaKuNPaB CaCagbrimaN. RTwsþIGrb‘Ítal;m:UelKulpþl;[nUvKMrUy:agTUlMTUlayénsm<½n§elah³. PaBTUlMTUlay énRTwsþIGrb‘Ítal;m:UelKulenH eBlxøHRtUv)aneKehAfa RTwsþIbg; (band theory) EdleyIgnwg

bgðajedaykaremIleTAelIGrb‘Ítal;lIcUm. enAkñúgCMBYkTI 3 eyIg)aneXIjfaGatUmlIcUmBIr)anrYmbBa©ÚlKñaenAkñúg pas]s μ ½nedIm,IbegáItCam:UelKulDIlIcUm. düaRkam Grb‘Ítal;m:UelKul EdlbgðajBIkarlayKñaénGrb‘Ítal; GatUm 2s BIrRtUv)anpþl;[enAkñúgrUb 4/1. ¬Grb‘Ítal; GatUmTaMgBIrRtUv)anbgðajenAxageqVg¦. \LÚvenHsnμt

faGrb‘Ítal;GatUménGatUmlIcUmbYn RtUv)anlayKña. mþgeTot vaRtUvEtmancMnYnGrb‘Ítal;m:UelKul s2σ dUceTA nwgGrb‘Ítal;GatUm2s Edr Grb‘Ítal;Bak;kNþalCasm<½n§ ehIyBak;kNþaleTotCabdism<½n§. edIm,Iecosvag

karbMBanviFankg;Tic famBlénGrb‘Ítal;TaMgLayminGacCadUcKña (degenerate) )aneT. Grb‘Ítal; s2σ mYyminGacmantémøfamBlBitdUcnwgfamBlGrb‘Ítal; s2σ mYyeTotenaHeT. rUb4/2 bgðajBIlT§plénkarerobcMGrb‘Ítal;.

rUb4/2 düaRkamGrb‘Ítal;m:UelKulsRmab;karrYmbBa©ÚlKñaénGatUmlIcUmTaMgbYn.

rUb4/1 düaRkamGb‘Ítal;m:UelKulsMrab;m:UelKulDIlIcUm ¬pas]sμ ½n¦

sm<½n§elah³

4-4

enAkñúgelah³RKIsþal;FM Grb‘Ítal;énGatUm n Edl n KWCacMnYnd¾FMRtUv)anlaycUlKña. Grb‘Ítal;TaMgenHmanGnþrkmμBaseBjvimaRtbIénelah³RKIsþal; b:uEnþBYkvaRtUv)aneKarB eKalkarN_sm<½n§dEdl. vanwgmanGrb‘Ítal;m:UelKul sn 22

1 σ ¬sm<½n§¦ nigGrb‘Ítal;m:UelKul sn 22

1 ∗σ ¬bdism<½n§¦. edaysarmancMnYnkMritfamBld¾eRcIndUcenH cenøaHrvagkMritnImYy² køayCaCitrYmcUlKñaCatMN. tMNenHRtUv)aneKehAfabg; (band). sRmab;lIcUm bg;Edl)an mkBIGrb‘Ítal;GatUm 2s nwgRtUv)anbMeBjBak;kNþal. KWfaEpñkénGrb‘Ítal; s2σ énbg;nwgRtUv )anbMeBj ehIyEpñkGrb‘Ítal; s2

∗σ nwgTeT ¬rUb4/3¦.

eyIgGacRsémemIlrUbPaBcmøgcrnþGKÁisnI)any:aggay dUcCakarTTYledayeGLic RtugénbrimaNd¾tictYcénfamBlEdlRtUvkaredIm,ItMeLIgvacUleTAkñúgGrb‘Ítal;bdism<½n§TeT. bnÞab;mk vaGacRtUv)anykecjedayesrIkat;tamTRmg;GatUmCacrnþGKÁisnI. RsedogKñaenH Edr PaBcmøgkemþAénelah³GacRtUv)anKiteXIjdUcCaeGLicRtugesrIEdldwkCBa¢ÚnfamBl bkERbBaseBjTRmg;elah³. eTaHbICay:agNak¾eday vamansar³sMxan;kñúgkarcgcaMfa karBnül; d¾BitR)akdén)atuPUtenHRtUvkarkarsikSasuICMerACagenHeTAelIRTwsþIbg;. enAkñúgCMBYkTI1 eyIg)aneXIjfaBnøWRtUv)anRsUb nigbeBa©jenAeBleGLicRtug pøas;TIBIkMritfamBlmYyeTAkMritfamBlmYyeTot. karbeB©ajBnøWRtUv)aneKsegáteXIjCa s,iúcbnÞat;. CamYynwgkMritfamBleRcInGenkenAkñúgelah³ vaswgEtmancMnYnKñanRBMEdnén PaBqøgkMritfamBl. CalT§pl GatUmenAelIépÞelah³GacRsUbCMhanrlkNak¾)an ehIy bnÞab;mkbeBa©jBnøWmþgeTotenACMhanrlkEtmYy dUcnwgeGLicRtugbeBa©jfamBldUcKñaenaH enAeBlEdlvaRtlb;mksNæanRKwHGIcwgEdr. ehtuenH RTwsþIbg; Bnül;BIBnøWrelagelah³. ebrüÚmk¾RtUveTAnwgKMrUbg;Edr. CamYynwgrUbsNæanGatUm [He]2s2TaMgGrb‘Ítal;m:UelKul

s2σ nig s2∗σ nwgRtUv)anbMeBjkEnøg. KWfa bg;Edl)anmkBIGrb‘Ítal;GatUm 2s EdlKgelIKña

nwgRtUv)anbMeBjTaMgRsug. CadMbUg karsnñidæannwgfa ebrüÚmminGacbgðajlkçN³elah³

rUb4/3 bg;Edl)anmkBIGb‘Ítal;GatUm edaykarrYmbBa©ÚlKñaénGatUmlIcUm n .

CMBYkTI4

4-5

edaysarEtvaK μanlMhenAkñúgbg;EdleGLicRtugGaceFVIclna)an. eTaHbICay:agNak¾eday bg;TMenr 2p KgelIbg; 2s EdleFVI[eGLicRtugmanclnakat;tamTRmg;elah³ ¬rUb4/4¦.

eyIgGaceRbIRTwsþIbg; edIm,IBnül;BImUlehtuEdlsarFatuxøH CaGñkcmøgcrnþGKÁisnI ehIyxøHeTotminEmn ehIysarFatuxøHeTotCasWmIkugDucT½r (semiconductor) ¬cmøgBak; kNþal¦. enAkñúgelah³ bg;KgelIKñaehIyGnuBaØat[eGLicRtugeFVIclnaedayesrI. enA kñúgGelah³bg;RtUv)anEjkdac;BIKña dUecñHBuMmanclnaeGLicRtugNaekIteLIgeT ¬rUb4/5a¦.

rUb4/5 düaRkamTRmg;bg; (a) Gelah³ (b) sWmIkugDucT½rkñúg nig(c) sWmIkugDucT½rminsuT§

FatuTaMgenHRtUv)aneKehAfaCasarFatuGuIsULg; (insulator). kñúgFatumYycMnYntUc bg;enH KW enACitKñaRKb;RKan; edIm,I[RtwmEtbrimaNtictYcénkarePJaceGLicRtugenAkñúgbg;TMenrenAelI ¬rUb4/5b¦. FatuTaMgenHRtUv)aneKsÁal;faCasWmIkugDucT½rxagkñúg intrinsic semiconductors. bec©kviTüaTMenIbrbs;eyIgBwgEp¥keTAelIkareRbIR)as;FatusWmIkugDucT½r ehIyva)ankøayCaman sar³sMxan; edIm,IsMeyaKsWmIkugDucT½rCamYynwglkçN³yfaRbePTxøaMg. enHGacRtUv)aneK

rUb4/4 bg;Edl)anmkBIGb‘Ítal; RBMEdn ¬2s nig 2p ¦ énebrüÚm

sm<½n§elah³

4-6

eFVIedaykarykFatuEdlmancenøaHbg;FM ehIybEnßmFatudéTepSgeTottictYc (impurity) Edl eKehAfa doping. FatuEdl)anbEnßmmankMritfamBlenAcenøaHkMritfamBlénFatupSM Ed;l )anbMeBjnigkMritfamBlEdlTeT¬rUb4/5c¦. bg;EdlminsuT§enHGacRtUv)anbBa©Úleday eGLicRtug enAkñúgbg;Edl)anbMeBjehIyeFVI[PaBcmøgxøHekIteLIg. edaysarmeFüa )ayenH lkçN³eGLicRTicénsWmIkugDucT½rGacRtUv)aneKEkERb edIm,IbMeBjnUvtMrUvkarNamYy. 4/3 TRmg;elah³ meFüa)ayEdlGatUmelah³pÁúMCitCamYyKñaCaRKIsþal; KWKYr[cab;GarmμN_ b:uEnþ edaymansar³sMxan;esμ IKñacMeBaHGñkKImIEr: vak¾pþl;[nUvmUldæanRKwHedIm,IBiPakSaBIkarpÁúMCit GuIy:ugenAkñúgsmasFatuGuIy:ug ¬EdleyIgnwgBiPakSaenAkñúgCMBYkTI5 cMNuc 5/5¦. KMnitén karbgÁúMCitRKIsþal;):an;s μanfaGatUmKWCaEsV‘rwg. enAkñúgelah³RkamGatUmRtUv)anerobcMCalMdab; CYrdEdl²EdlRtUv)aneKehAfa bNþajRkam. karbgÁúMCitGatUmelah³KWBitCabBðaaenAkñúg FrNImaRt. KWWfaeyIgRtUvKitBIPaBxusKñaCaeRcInEdlEsV‘manTMhMdUcKñaGacRtUv)anerobcM. vamankargayRsYlbMputedIm,IKiteXIjBIkarcMerobCYrGatUm edayeFVIkarerobcMRsTab; mYy ehIybnÞab;mkdak;RsTab;bnþeTotBIelIva. karerobcMsamBaØbMputEdlGaceTArYc KWfaGatUmenAkñúgRKwHRtUv)anpÁúMCitRCugTl;RCug. RsTab;bnÞab;énGatUmRtUv)andak;edaypÞal; BIelIRsTab;xageRkam. kartMerobenHRtUv)aneKsÁal;faCa bgÁúMhab;KUbsamBaØ (simple cubic

packing) (sc)¬rUb4/6¦ b¤ehAfaKUbedIm primitive cubic . GatUmnImYy²RtUv)anb:HCamYynwg GatUm4epSgeTot enAkñúgbøg;rbs;va bUkCamYynwgGatUm1xagelI nig1xageRkam naM[ GatUmCitxagmansrub6. CalT§plvaRtUv)aneKniyayfaGatUmnImYYy²mancMnYnkUGrDINasüúg cMnYn 6.

karerobcMKUbFmμtaKwminsUvCaENneT ehIyvaRtUv)aneKsÁal;faRtwmEtcMeBaHb:ULÚj:Úm enAkñúgTRmg;elah³ ebIeTaHbICaeyIgnwgeXIjenAkñúgemeronTI5 vaRtUv)anrkeXIjenAkñúgsmas FatuGuIy:ugxøH. karerobcMpÁúMCitKUbepSg KWRtUvdak;RsTab;TIBIrénGatUmeTAelIrn§TMenrénRsTab;

rUb4/6 karevcx©b;KUbFm μta. RsTab;bnÞab; RtUv)andak;enAxagelIRsTab;CYrTImYy

CMBYkTI4

4-7

TImYy. bnÞab;mk RsTab;TIbIdak;enABIelIrn§énRsTab;TIBIr EdlekIteLIgy:agc,as;elIRsTab; TImYy. karerobcMEdlENnCagenHRtUv)aneKehAfa KUbp©itxagkñúg (body-centered cubic)

(bcc) ¬rUb4/7¦. GatUmnImYy²RtUv)anb:HedayGatUmbYnxagelI nigbYnGatUmxageRkambøg; rbs;va. dUecñH pþl;plCacMnYnkUGrDINasüúg 8.

lT§PaBEdlGacmanBIrepSgeTotKWBwgEp¥kelIkartMerobCaqekaNsRmab;RsTab;GatUm nImYy². GatUmnImYy²RtUv)anrMuB½T§edayGatUm6enACitxagenAkñúgbøg;. enAkñúgkartMerobCa qekaN rn§TMenrenAcenøaHGatUmTaMgLayKWCitKñaxøaMg ebIeRbobeFobeTAnwgkartMerobCaKUb ¬rUb4/8¦.

rUb4/8 RsTab;TI1énkartMerobCaqekaN

enAeBlEdlRsTab;qekaNTI2RtUv)andak;elIRsTab;TI1 vaminGaceTArYceTkñúgkar dak;GatUmTaMgLayelIrn§TaMgGs;énRsTab;TI1. CakarBit RtwmEtrn§TMenrBak;kNþalb:ueNÑaH EdlGacRtUv)anRKbBIelI. RbsinebIRsTab;TI3RtUv)andak;elIrn§TMenrénRsTab;TI2 dUecñHvaRtUv )andak;enAxagelIRsTab;TI1 bnÞab;mkkartMerobCa pÁúMCitqekaN (hexagonal close-packed)

(hcp)RtUvekIteLIg. RsTab;TI4RtUv)andak;BIelIRsTab;TI2. dUecñH vaRtUv)aneKsÁal;fa CakarbgÁúMhab; abab ¬rUb4/9¦. kartMerobpÁúMCitCaqekaNepSg Tak;TgeTAnwgkardak;RsTab;TI3enABIelIrn§TMenrén RsTab;TI1 nigTI2. bnÞab;mkRsTab;TI4mankartMerobdUcKñanwgRsTab;TI1Edr. kartMerob

rUb4/7 bgÁúMCitKUbp©itenAxagkñúg. RsTab;TIBIr ¬pat;BN’¦ RtUv)andak;elIrn§énRsTab;TImYy ehIyRsTab;TIbI dak;xag elIrn§énRsTab;TIBIr.

sm<½n§elah³

4-8

abcabc RtUv)aneKsÁal;Ca pÁúMCitKUb (cubic close-packed) (cpp) b¤k¾ KUbp©itépÞxagmux (face-

centered cubic) (fcc) ¬rUb4/10¦. karpÁúMCitTaMgBIrEdlBwgEp¥kelIkartMerobCaqekaNenH mancMnYnkUGrDINasüúg 12.

RbePTénkarpÁúMCit cMnYnkUGrDINasüúg nigPaKryénkarbMeBjénmaDsrub RtUv)an bgðajenAkñúgtarag4/1. karbMeBjkEnøgEdles μ I60PaKrymann½yfa 60PaKryénmaDRkam KWRtUv)andak;bMeBjedayGatUm ehIylMhcenøaHGatUmes μInwg40PaKry. dUecñH PaKryénkar bMeBjGatUmkan;Etx<s; GatUmk¾kan;EtRtUv)anpÁúMCit²KñaEdr. tarag4/1 lkçN³énRbePTénkarpÁúMCitGatUmxus²Kña

RbePTbgMÁú cMnYnkUGrDINasüúgcMnYn karbMeBj (%)

KUbsmBaØ (sc) 6 52

KUbp©itxagkñúg (bcc) 8 68

pÁúMCitqekaN (hcp) 12 74

pÁúMCitKUb b¤KUbp©itépÞxagmux (ccp/fcc) 12 74

elah³PaKeRcInmankartMerobNamYykñúgcMeNamkartMerobTaMgbIEdlmanPaBENn (bcc, hcp, fcc). b:ULÚj:Úm KWCaelah³EtmYyKt;EdlmankarpÁúMCitCaKUbsamBaØ. elah³xøH

rUb4/10 kartMerobCapÁúMCitKUbmanRsTab;TI3 ¬TItaMgEdlmandak;sBaØapáay¦EdlRtUv)an dak;elIrn§TMenrénRsTab;TI1 nigTI2.

rUb4/9 enAkñúgkarevcx©b;CaqekaNRsTab;TI2 RtUv)andak;BIelIrn§TMenrqøas;KñaénRsTab;TI1. kartMerobCapÁúMCitqekaNTak;TgeTAnwgkardak; RsTab;TI3 ¬TItaMgEdlmandak;sBaØapáay¦ elI kMBUlRsTab;TI1.

CMBYkTI4

4-9

CaBiess elah³EdlsßitenAxagsþaMédéntaragxYb mankartMerobGatUm ekag b¤minsþg;da. KMrU EsV‘rwgénkarpÁúMCitminGac[eyIgeFIVkarTsSn_Tayfa kartMerobGatUmBiessRbePTNa Edl elah³nwgmanenaHeT. b:uEnþ vahak;dUcCamanviFanTUeTA EdlfaenAeBlEdlcMnYneGLicRtug RsTab;eRkAekIneLIg kartMerobGatUmEdlmankarcUlcitþpøas;bþÚrBI bcc eTA hcp ehIycug eRkayKW fcc. rUb4/11 bgðajkarerobcMpÁúMCitGatUmTUeTAsRmab;elah³. karerobcMpÁúMCitGatUm sRmab;elah³mYycMnYnKWBwgEp¥kelIsItuNðPaB. ]TahrN_ EdkmanTRmg; bcc ¬ )iron−α enAsItuNðPaBbnÞb; ehIyTRmg;enHbþÚreTACaTRmg; fcc )( iron−γ kalNasItuNðPaBelIs 910ºC ehIyk¾Rtlb;eTATRmg; bcc vij )( iron−δ enAsItuNðPaBRbEhl 1390ºC. dUcEdleyIg)aneXIjenAkñúgemeronTI14 cMNuc14/23 karGaRs½ynwgsItuNðPaBénkarpÁúMCit GatUmKWCasar³sMxan;BiessénkrNIsMN):ahaMg.

rUb4/11 EpñkéntaragxYb EdlbgðajkartMerobGatUmefr énelah³enA SATP

4/4 ftÉkta Unit cell

kartMerobd¾samBaØbMputénEs‘V EdlenAeBlEdlmankartMerobdEdl² nwgbegáIteLIg vijTRmg;RkamTaMgmUl EdlRtUv)aneKehAfaftÉkta. ftenHKWgayRsYlnwgemIleXIjbMput enAkñúgkrNIKUbFmμta¬rUb4/12¦. enAkñúgftÉkta eyIg)ankat;KUbmYyBIcMNuckNþalén GatUm8. enAxagkñúgftÉktaxøÜnvaman8duMGatUm EdlduMnImYy²tMNag[mYyPaKR)aMbIén GatUm. edaysarEt 1)8

1(8 = eyIgGacniyayfaftÉktanImYy²manGatUmmYy. rUb 4/12 ftÉktaKUbEdlsamBaØ

sm<½n§elah³

4-10

edIm,ITTYl)anftÉktasRmab;KUbp©itxagkñúg eyIgRtUvEtykRkumEdlFMCagenH KWRkum EdlbgðajTRmg;RsTab;bIdEdl². karkat;KUbmYypþl;[nUvGatUmkNþalmYYy CamYynwg GatUmmYyPaKR)aMbI cMnYn8enARKb;RCug. dUecñH ftÉktaman 1 + )8

1(8 Edles μ I nwg2GatUm ¬rUb4 /13¦.

rUb 4/13 ftÉktaKUbp©itxagkñúg rUb 4/14 ftÉktaKUbp©itépÞxagmux

cMeBaHkarBinitüBic½ydMbUg karerobcMpÁúMCitKUbmin)anpþl;[ftÉktasamBaØeT. eTaHbI Cay:agNak¾eday RbsinebIcMNitmYyRtUv)anykecjBIRCugénbNþajKUbp©itépÞxagmux eyIg Gacsg;KUbp©itépÞxagmux EdlmanGatUmmYyenARCugnImYy² ehIyGatUmmYyenAcMkNþal muxnImYy² ¬rUb4/14¦. enAeBlEdleyIgeFVIdUcenH KUbmanbMENk )8

1(8)21(6 + Edlesμ I

nwgbYnGatUm.

elah³cgcaM ³ rUbragénvtßúenAGnaKt ebIeTaHbICaviTüasaRsþCaTUeTARtUv)aneKBN’nafaCakarbnþqøgkat;tamkarrIkcMerInKMnit )anl¥k¾eday karrkeXIjEdlmancMnYnKYr[PJak;ep¥IlénkarrkeXIjviTüasaRsþ KWminGac sgÇwmTukeT. ]TahrN_mYykñúgcMeNam]TahrN_d¾KYr[cab;GarmμN_ énmuxgaredayécdnü énviTüasaRsþ KWkarrkeXIj elah³cgcaM (memory metal) . erOgenHvaekIteLIgeday sarEteKalbMNgkñúgkarbegáItsMelah³ EdlFn;nwgbMEbksRmab;k,almIsuIlrbs;TahaneCIg TwkGaemric. elak William J. Buehler Caelah³viTU )anrkeXIjsMelah³ Edlmanm:Ules μ I KñaénTItannignIEkl BitCamanlkçN³EdlKat;RtUvkar. Kat;dak;eQ μaHsMelah³enHfa nITINul nitinol (nickel titanium Naval Ordnance Laboratory). edIm,IbgðajBIlkçN³nITINul Kat;)anyksMelah³Evg ehIyRtg;ehIybt;vaCarUbrag . Kat;nwgbgðajrebob Edl elah³GacRtUv)aneFVI[ywtdEdl²edayminmankar)ak;Ebk. PaBEdlGacbt;Ebn)anén

CMBYkTI4

4-11

elah³KWCalkçN³Edlmansar³RbeyaCn_Nas;. enAeBlEdlmaneFVIkarbgðajdUcenaHGñk cUlrYm)anbegáItEdkekHehIydutelah³enaHbnþicmþg². GVIEdleFVI[Gñkral;KñaPJak;ep¥IlenaH KWfabnÞHelah³enaHmansPaBRtg;vij¡ elah³enH)ancgcaMrUbragedImrbs;va. CamYynwgelah³Fmμta karbt;vaGacbNþal[RkamCitxagrGilelIKña. nITINul manTRmg;RkamminFmμtaEdlfavamankartMerobbNþajKUbsamBaØénGatUmnIEkl CamYynwg GatUmTItanenAcMkNþalKUbnIEklnImYy² cMEnkGatUmTItanxøÜnvaKWsßitenAbNþajKUbsamBaØ CamYynwgGatUmnIEklenAcMkNþalKUbTItannImYy²¬rUb4/15¦. TRmg;cak;eRsHenHKWCaGVIEdl min[RkamenACitxagBIkarpøas;TIeTAkan;RkamepSgeTot nigeFVI[manlkçN³yWtxøaMgénvtßú.

rUb4/15 pas austenite énnITINul. GatUmnIEklmankartMerobCaKUbCamYynwgGatUm TItanj:ÚmenAcMkNþalKUbnImYy². GatUmTItan ¬BN’ex μA¦ mankartMerobCaKUbEdlcak;eRsH CamYynwgGatUmnIEklenAcMkNþalKUbnImYYy². enAsItuNðPaBx<s; passuIemRTI ¬austenite) KWmanesßrPaB b:uEnþenAsItuNðPaBRtCak;sMelah³ rgkarERbRbYlpaseTACaKUbrmYl ¬pas martensite). enAkñúgpasenH Rkam martensite

GacBt;bt;Ebn)anRKb;RKan;Edlelah³FM GacRtUv)aneFVI[ekagmþgehIymþgeTotedayK μan eFVI[)ak;Ebk. kardutkemþAtic²GacRtUv)aneRbIedIm,IeFVI[RkamRtlb;eTArkPaB edImvij. edIm,IeFVI[manTRmg;f μ I elah³RtUvEt)andutkemþAenAxagelIsItuNðPaBqøgpasrbs;va ¬Edlva GaRs½ynwgpleFobm:UlBitR)akdénFatupSMTaMgBIr¦. nITINulmankareRbIR)as;CaeRcIn rYmTaMgkareRbIR)as;enAkñúgkarpliteRKOgeFVI[eFμj Rtg;nigKMrbkBa©k;Ev:ntaEdlmingayEbk nigmanRbsiT§PaBgayRsYleRbICagmun. cenÞos sV½yRbvtþ KWCakareRbIR)as;mYyepSgeTot. GñkCMnajxagRtecokGacbt; ebIk cuccenÞos ehIydak;vaeTAkñúgRtecokrbs;GñkCMgWrhUtTal;EtcugenaHRtUv)anh‘MuB½T§edayvtßúEdlmkBIxag eRkA ehIybnÞab;mkdak;crnþd¾TabeTAkan;ExS. kareFVI[ExSeLIgkemþA ehIynwglT§pl

GatUmnIEkl

GatUmTItan

sm<½n§elah³

4-12

Rtlb;eTATRmg;GatUmedImnwgbNþal[cugbiTenAxagelIvtßú dUecñHvaGacRtUv)andkecj edaysuvtßiPaB. 4/5 sMelah³ Alloys

karrYmbBa©ÚlKñaénelah³rwgBIr b¤eRcInRtUv)aneKehAfa sMelah³. cMnYnsMelah³Edl Gacman KWeRcIn. sMelah³edIrtYnaTIy:agsMxan;enAkñúgCIvitrbs;eyIg b:uEnþKImIviTUkMrnwgGFib,ay BIvaNas;. GatUmenAkñúgsMelah³RtUv)anP¢ab;CamYyKñaedaysm<½n§elah³ dUcnwgFatuelah³pSM déTeTotEdr. sm<½n§enHKWRsbeTAnwgsm<½n§kUv:aLg;énGelah³. sm<½n§kUv:aLg;P¢ab;CamYyKñanUv m:UelKulEdl)anbegáIteLIgBIKUénFatuGelah³epSgKña k¾dUcCaP¢ab;m:UelKulEdl)anBIKUGela h³dUcKñaEdr. RsedogKñaenH sm<½n§elah³énsMelah³P¢ab;CamYyKñanUvGatUménFatuelah³ epSgKña. sMelah³manBIrRbePT³ sUluysüúgrwg nigsmasFatusMelah³. kñúgsUluysüúgrwg elah³rlayRtUvlayKñaedIm,IbegáItCal,ayes μ Isac;. edIm,IbegáItCasUluysüúgrwg GatUmén elah³TaMgBIrRtUvmanTMhMb:unKña ehIyRkamelah³RtUvEtmanTRmg;dUcKña. bEnßmBIelIenH elah³RtUvmanlkçN³KImIRsedogKña. masnigTg;Edg Ca]TahrN_ begáItnUvpasEtmYytamPaKryNak¾edayBI 100 PaK rymas nig 100 PaKryTg;Edg. elah³TaMgBIrenH mankaMGatUmRsedogKña ¬masmankaM 144pm nigTg;EdgmankaM 128pm ¦ehIyelah³TaMgBIrenHmanTRmg;KUbbiTCit. sMN nigsMN):ahaMgmankaMelah³RsedogKñaNas; ¬sMNmankaM 175pm nigsMN):ahaMgmankaM 162pm¦b:uEnþsMNmanTRmg;KUbp©itépÞxagmux ehIysMN):ahaMgmanTRmg;pÁúMCitCakuMpøic. elah³mYyEdleLIgRkamCamYynwgelah³epSgeTot KWmantictYcNas;. elah³sRmab;pSar b:MBg;TwkmansMN):ahaMg30PaKry nigsMN 70PaKry ehIyenHKWCaPaBminGaclaycUlKña )anrbs;vaEdlGac[vaedIrtYnaTICakavelah³. kMLúgeBleFVI[GgÁFaturavRtCak; vaman cenøaHRbEhlCa100ºC EdleFVI[kMNkRkamekIteLIg. sUluysüúgrwgminGacmansMN )a:haMgelIsBI20PaKryeT. CalT§pl RkamKWmaneRcInenAkñúgsMNrlay ehIysUluy süúgEdlenAsl;mansItuNðPaBkMNkTabCag. lkçxNÐenHGac[GñkpSarbMBg;TwkeFVIkar CamYYynwgelah³pSar)an.

CMBYkTI4

4-13

tarag4/2 sMelah³TUeTA eQ μaH smasPaKpSM¬PaKry¦ lkçN³ kareRbIR)as; Brass Tg;Edg 70-85/ sgá½sI

15-30 rwgCagTg;EdgsuT§ bMBg;Twk

mas 18-karat; mas75/ R)ak;10-20/ Tg;Edg5-15

rwgCagmassuT§ ¬24karat¦

eRKOgGlgáar

EdlEfbGIunuc Edk65-85/ RkUm12-20/ nIWEkl 2-15/ m:g;kaENs1-2/ kabUn0/1-1/ suIlIcUm0/5-1

Fn;nwgPaBeRcH ]bkrN_epSg²/ sMPar³KImI

enAkñúgkrNIxøHEdlTRmg;RkaménsmasPaKpSMxusKña karlayelah³rlaypþl;CakMN énpasesÞIrsüÚemRTI. ]TahrN_ Tg;Edg nigs½gásIbegáItCasmasFatubI³ CuZn, Cu5Zn8, nig CuZn3. tarag4/2 bgðajnUvsMelah³TUeTAmYycMnYn smasPaKpSM nigkareRbIR)as;. bBaØtþisMxan;

• sm<½n§elah³RtUv)anBiBN’na)any:agl¥bMputedayeRbIRTwsþIbg; Edl)anmkBIRTwsþI Grb‘Ítal;m:UelKul.

• GatUmelah³GacpÁúMCit)anEtbYnrebob. • kartMerobpÁúMCitTaMgenHmanÉktasamBaØftÉkta. • sMelah³ Cal,ayénelah³BIr GacCasUluuysüúgrwg b¤k¾smasFatusMelah³.

BaküKnøwH sMelah³ alloy 4-12

bg; band 4-4

RTwsþIbg; band theory 4-3

KUbp©itxagkñúg body-centered cubic (bcc) 4-7

sm<½n§elah³

4-14

sMriT§ bronze 4-1

bNþajRkam crystal lattice 4-6

pÁúMCitKUb cubic close-packed (cpp) 4-8

KMrUsmuRT-eGLicRtug electron sea model 4-3

KUbp©itépÞxagmux face-centered cubic (fcc) 4-8

pÁúMCitqekaN hexagonal close-packed (hcp) 4-7

GuIsULg; insulators 4-5

sWmIkugDucT½rxagkñúg intrinsic semiconductors 4-5

PøWrelagelah³ metallic luster 4-4

nITINul nitinol 4-10

sWmIkugDucT½r¬cmøgBak;KNþal¦ semiconductor 4-5

pÁúMCitKUbsmBaØ simple cubic packing 4-6

rlayesI sinter 4-2

ftÉkta unit cell 4-9

lMhat; 4/1 cUr[niymn½yBaküTaMgenH (a) KMrUsmuRTeGLicRtugénsm<½n§ (b) ftÉkta (c) sMelah³. 4/2 Bnül;BIGtßn½yénBaküdUcteTA (a) bNþajRkam (b) cMnYnkUGrDINasüúg (c) Gam:ahÁam. 4/3 etIlkçN³sMxan;TaMgbIénelah³manGVIxøH? 4/4 etIkareRbIR)as;y:agTUlMTUlayTaMgbYny:agénelah³manGVIxøH? 4/5 edayeRbIdüaRkambg; Bnül;faetIm:aej:süÚmGacbgðajlkçN³Caelah³edayrebobNa enAeBlEdlbg; 3s rbs;vaRtUv)aneBjTaMgRsug? 4/6 cUrKUsdüaRkambg; sRmab;GaluymIj:Úm? 4/7 cUrBnül;faetIehtuGVIlkçN³elah³minekIteLIgenAkñúgpas]s μ ½n? 4/8 etIrUbmnþEdlGacmansRmab;b:UtasüÚmenApas]sμn½KWGVI? cUrKUrdüaRkamGrb‘Ítal;m:UelKul edIm,Ibgðajehtuplrbs;Gñk. 4/9 etIkartMerobRsTab;TaMgBIrRbePTenAkñúgelah³KWGVIxøH? etImYyNamankarpÁúMCitCitCag? 4/10 etIGVICaPaBxusKñaenAkñúgTRmg;RsTab; rvagkartMerobpÁúMCitKUb nig pÁúMCitqekaN?

CMBYkTI4

4-15

4/11 cUrKUrftÉktaKUbsamBaØmYYy ehIybgðajrebobEdlcMnYnGatUmkñúgmYyftÉkta GacTajrk)an. 4/12 cUrKUrftÉktaKUbp©itxagkñúg ehIybgðajrebobEdlcMnYnGatUmkñúgmYyftÉktaGac Tajrk)an. 4/13 etIlkçxNÐGVIEdlcaM)ac;sRmab;karbegáItsMelah³sUluysüúgrwg? 4/14 cUr[mUlehtuBIrEdls½gásI nigb:UtasüÚmminGacbegáItCasMelah³sUluysüúgrwg. lMhat;elIsBImYldæanRKwH 4/15 eRbIR)as;FrNImaRtedIm,Ibgðajfa RbEhlCa48PaKryénbNþajKUbsamBaØ KWCalMh TeT. 4/16 eRbIR)as;FrNImaRtedIm,Ibgðajfa RbEhlCa32PaKryénbNþajKUbp©itxagkñúg

KWCalMhTeT. 4/17 enAkñúgÉktaKUbp©itépÞxagmux GatUmEtgEtb:Hkat;tamGgát;RTUgénmux. RbsinebIkaM GatUm r cUrKNnaRbEvgRCugnImYy²énftÉkta. 4/18 enAkñúgftÉktaKUbp©itxagkñúg GatUmEtgEtb:Hkat;tamGgát;RTUgBIRCugmYykat;tam cMNuckNþalénftÉktaeTARCugTl;mux. RbsinebIkaMGatUm r cUrKNnaRbEvgRCugnImYy²én ftÉkta. 4/19 RkUmbegáItbNþajKUbp©itxagkñúg EdlenAkñúgenaHRbEvgEKménftÉkta KW 288pm. cUrKNna (a) kaMelah³énGatUmRkUm nig (b)dg;suIeténelah³RkUm. 4/20 GatUmelah³)arüÚmRtUv)anerobcMCaftÉktaKUbp©itxagkñúg. cUrKNnakaMGatUm)arüÚm RbsinebIdg;suIetGatUm)arüÚmKW 3.50g.cm-3. cMnaM³ eRbIcMelIyGñkenAkñúglMhat; 4/18. 4/21 GatUmelah³R)ak;RtUv)anerobcMCaftÉktaKUbp©itépÞxagmux. cUrKNnakaMGatUmR)ak; RbsinebIdg;suIetGatUmR)ak;KW 10.50 g.cm-3. cMnaM³ eRbIcMelIyGñkenAkñúglMhat; 4/17. 4/22 cUrENnaMfaetIGVICabBaðaCamYynwgkardak;épÞelah³s¥atBIreTAlMhxageRkA. cemøIy 4.1 (a)KMrUmYyEdlkñúgenaHvaRtUv)aneKcat;Tukfaelah³manGIuyu:gelah³CamYyeGLicRtug

esrI. (b) bMENktUcbMputénbNþajRkamEdlnwgbegáIteLIgvijnUvTRmg;TaMgRsug.

sm<½n§elah³

4-16

(c) karbBa©ÚlKñaénelah³rwgBIr b¤eRcIn. 4.5 PaBRtYtsIuKñaénbg; 3s nig 3p Edlmann½yfaeGLicRtugkñúgbg; 3s eBjGacehor

eTAkñúgbg; 3p EdlGac[eGLicRtugeFIVclnatambNþajRkam.

4.9 KUb nigqekaN EdlqekaNRtUvpÁúMCitCag. 4.13 GatUmRtUvmanTMhMdUcKña EdlBYkvaRtUvTTYl)anTRmg;dUcKña ehIyBYkvaRtUvman

KImIRsedogKña. 4.17 RbEvgépÞviCÆekaNnwgCa 4r. edayeRbIRTwsþIbTBItaK½r RbEvgéncugÉktanwgCa

[4/(2)½]r = 2.83r

4.21 ÉktaKUbp©itépÞxagmuxmanGatUmbYn. dUcenH ma:s = 123

1

mol1002.6molg9.1074

−

−

×⋅× = 7.17 × 10−22 g

maD = 3

22

cmg50.10g1017.7−

−

⋅×

= 6.83 × 10−23 cm3 = 6.83 × 107 pm3

RbEvgénRCug = 3√(6.83 × 107 pm3) = 409 pm

edayeRbIlT§plBIlMhat;TI 4.17, kaMénGatUmR)ak; = (409 pm)/(2.83)

= 145 pm.