Заглавная страница Избранные статьи Случайная статья Познавательные статьи Новые добавления Обратная связь КАТЕГОРИИ: АрхеологияБиология Генетика География Информатика История Логика Маркетинг Математика Менеджмент Механика Педагогика Религия Социология Технологии Физика Философия Финансы Химия Экология ТОП 10 на сайте Приготовление дезинфицирующих растворов различной концентрацииТехника нижней прямой подачи мяча. Франко-прусская война (причины и последствия) Организация работы процедурного кабинета Смысловое и механическое запоминание, их место и роль в усвоении знаний Коммуникативные барьеры и пути их преодоления Обработка изделий медицинского назначения многократного применения Образцы текста публицистического стиля Четыре типа изменения баланса Задачи с ответами для Всероссийской олимпиады по праву Мы поможем в написании ваших работ! ЗНАЕТЕ ЛИ ВЫ?
Влияние общества на человека
Приготовление дезинфицирующих растворов различной концентрации Практические работы по географии для 6 класса Организация работы процедурного кабинета Изменения в неживой природе осенью Уборка процедурного кабинета Сольфеджио. Все правила по сольфеджио Балочные системы. Определение реакций опор и моментов защемления |
CMCTeMa c HepacTBOpMMblMM (HeB38MMOAeMCTBYIOIQMMM) KOMnOHeHTaMM
IlpuMepaMH TaKHX cucTeM HBJIHIOTCH Cu-C, W-Ag, W-Cu, Mo-Cu H.n;pyrne. BJI. IluHec c<t>opMyJIHPOBaJI TepMOAHHaMHlJeCKoe ycJIOBHe rrpHrreKaHHH.n;eyx lJaCTHU pa3HOpO,ll;HblX HeB3aHMO,LI,eHCTBYIO ll(HX KOMIIOHeHTOB: (LAB< l a.A + a.B l ' (14.41) T.e. IIOBepXHOCTHrul 3HeprnH o6pa30BaBIIIeHCH Me)l($a3HOH rpaHHUbl AB,LI,OJI)l(Ha 6b Tb MeHbIIIe, t.1eM cyMMa rroeepxHoCTHb X 3HeprnH: qac THU A u B; B rrpoTHBHOM CJiyqae rropoIIIKoeoe reJio crreKaTbCH He 3 4 BO)l(,ll;aeTc» yeeJIHlJeHHeM ee o6'beMa Ha 22 % (e pacqere Ha 1 MOJib Si3N4), H 3a ClJeT 3Toro npoHcxo.n;HT qacTHlJ:Hoe 3anoJIHeHHe rropoeo- ro npocTpaHCTBa. IlJIOTHOCTb no- poIIIKoeoro reJia. nocJie crreKaHIDI 6y,LI,eT. MexaHH3M u KHHeTHKa npuneKaHH» oKa3bIBaIOTCH cymecTBeHHO pa3JIHlJHb MH,ll,JIH,ll,Byx B03MO)l(Hb X CJiyqaeB npH co6JIIO,LI,eHHH ycJIO BHH (14.41): T, r--.......a:
3aBHCHT OT HCXO,ll;HOH nopHCTOC TH $opMOBKH, $paKIJ,HOHHOro COCTaea nopoIIIKa KpeMHHH, TeM- rrepaTYPHo-epeMeHHb'X ycJIOBHH a. AB< I a.A - a.B l ' (1.AB> I (1.A - (1.B I. (14.42)
(14.43)
1000 0 + (Mo)
v;V, % 6
PHc. 254..[J;HarpaMMa COCTOHHIDI (a) H KOHUeHTpaUHOHHaH JaBHCHMOCTb yca,nKH (6) nopoUIKOBhIX ren CHCTeMhI Ni-Mo IlpH 1200 'C 222 cneKaHIDI. CeoH:cTBa MarepHaJIOB, o6pa- 30BaHHb X paccMaTpHBaeMblMH CHCTeMaMH KOMIIOHeHTOB nocJie crreKaHHH, 3aBHCHT OT ueJioro pH,n;a $aKTopoe: IIOJIHOTblfOMO reHH3aIJ,HH B o6JiaCTH orpaHH lJeHHb X TBep,n;blX paCTBOpOB, rro pHCTOCTH, COBepIIIeHCTJ;Ja Me)l( $a3Hb X H O,ll;HO$a3Hb X KOHTaK TOB H.n;p. PoJib rerepo.n;H$$y3HH CBO,ll;HTCH K o6ecrrelJeHHIO Bb paB HHBaHIDI KOHUeHTpaIJ,HH 3JieMeH TOB B 06JiaCTHX orpaHHlJeHHOH paCTBOPHMOCTH, rrpHlJeM,ll;OCTH )l(eHHe roMoreHHOCTH B 60Jib lllHHCTBe CJiyqaee)l(eJiaTeJibHO (rrpH rrpe.n;eJibHblX KOHUeHTpa UHHX MHOrne CBOHCTBa orpaHH- B CJiyqae, KOr,LI,a BblIIOJIHHeTCH COOTHOIIIeHHe (14.42), 3HepreTH lJeCKH ueJiecoo6pa3HO IIOKpblTHe rroeepXHOCTH lJaCTHUhl eemecTBa c 6oJibllleH IIOBepXHOCTHOH 3Heprneu eemecTBOM c MeHbllleH rroeepx HOCTHOH 3Heprneu (pHc. 255). BHat.JaJie qacTHua TaKoro eemecrea (rrycTb 3TO 6y,LI,eT eemecTBo B) rroKpoeTCH cJioeM aroMoB BToporo eemecTBa (e HaIIIeM cJiyqae eemecTBa A) c rroMOll.lbIO MexaHH3Ma rroeepxHOCT HoH: AH$$y3HH HJIH rrepeHOCOM qepe3 ra30BYIO $a3y; rrpH 3TOM <t>op Ma HCXO,ll,Hb X t.JaCTHU coxpaHHeTCH. 3aTeM KOHTaKTHrul IIJIOll(a,ll;b Me)I(-
PHc. 255. CxeMaTw1ecKoe HJo6pa)l(eHHe 3Tanos (a - z) npHneKaHHSI 'laCTHU .UY qacnu.1,eH: A H qacTuueH: B, noKphITOH CJIOeM BemecTBa A, yBeJIH quBaeTC.st, qTO conpOBO)l(,lJ,aeTC.SI yMeHbllleHHeM cyMMapHOH noBepx HOCTH B CHCTeMe A-B H, COOTBeTCTBeHHO, ee CB060,lJ,HOH 3HeprHH. K1rneTHKa 3Toro 3Tana npuneKaHH.SI 6JIH3Ka K KHHeTHKe npuneKaHH.SI ,lJ,Byx 0,lJ,HOPO.ll.HhlX cct>epuqeCKHX qacTHU, XOT.SI BeIUeCTBO B o6JiaCTh npHKOHTaKTHOfO nepellleHKa 6y.n.eT nocrynaTb OT O,lJ,HOH nopolllHHKH A, a He OT o6oux qacTHU A H B. CJIH.SIHHe cct>epuqecKHX qacTHU A u B .UOJI)l(HO JaBeplllHThC.SI o6pa3oBaHHeM cct>epuqecKoro reJia, MPOM KO Toporo 6y.n.eT qacTHUa B. Kor.n.a HH)l(ff.ff.SI rpaHHUa BeJIHqHHhI a.A8 Ja.n.aeTc.st ycJioBHeM (14.43) (6oJiee pacnpocTpaHeHHhlH CJiyqaH:,lJ,JI.SI npaKTHKH nopOlllKOBOH Me TaJIJIYPrHH), npuneKaHHe qacTHU cymecTBeHHO OTJIHqaeTC.SI OT pac CMOTpeHHOfO. Pacnpe.n.eJieHHe BeIUecTBa A H B B o6JiaCTH KOHTaKTHoro nepellleH:Ka onpe.n.eJI.steTc.st rpaHuueH:, HMeiomeH: ct>opMy yqacTKa cct>e phIc BhITIYKJIOCThIO B CTOpoHy qacTHUhl c MeHbllleH noBepXHOCTHOH 3HeprueH:, H nopOlllHHKa BemecTBa c 60JibllleH noBepXHOCTHOH 3Hep rueH: KaK 6b1 B.UaBJIHBaeTC.st B nopolllHHKY BemecTBa c MeHhllleH: no BepxHOCTHoH: 3HeprueH:. IloJIHoe yTIJIOTHeHHe nopolllKOBoro TeJia npu 3TOM He,lJ,OCTHraeTC.SI. B o6meM cJiyqae npouecc ynJIOTHeHH.st nopolllKoBoro TeJia B Haqa Jie H30TepMuqecKoro cneKaHH.SI MO)l(eT 6hITh OTIHCaH ypaBHeHHeM
(14.40). 0.n.HaKO 3aBHCHMOCTh napaMeTpOB 3T0f0 ypaBHeHH.SI OT TeMne paryphl cymecTBeHHO HCKa)l(eHa H 06b1qHo He COOTBeTCTByeT TeMne paTypHOH 3aBHCHMOCTH.ll.Jl.SI 0,lJ,HOcPa3HhlX nopOlllKOBh X TeJI.
KoHmpoAbHble eonpocbl 1. KaKOBhI.UBIUHe CHJihI npu TBep.n.oct>aJHOM cneKaHHH MHO roKoMnoHeHTHh X nopOlllKOBh X TeJI? 2. PaccKa)l(HTe 0 TBep.n.oct>aJHOM cneKaHHH CHCTeM c TIOJIHOH B3a HMHOH paCTBOpHMOCTh IO KOMTIOHeHTOB. 3. KaKOBhIMexaHH3MhIct>opMHpoBaHH.SI MexqacTHqHhIX cB.st3eH: npu TBep.n.oct>aJHOM cneKaHHH CHCTeMblc HepacTBOpHMhlMH KOMilOHeHTa MH?
PeKoMeHaameAbHblii 6u6Auo2pa<jJu11ecKuii cnucoK 1. CKopoxoa B.B., CoAOHUH C.M. <l>H3HKo-MeTaJIJiypmqecKue ocHOBhI cneKaHH.st nopolllKOB. - M.: MeTaJIJiyprH.st, 1984. -159 c. (c. 76-99). 2. AHapueecKuii P.A. IlopolllKOBoe MarepHaJIOBe.n.eHue. - M.: MeTaJI Jiypm.st, 1991. - 205 c.(c. 94- 104). rnaea 15. >KMAKo<t>aaHoe cneKaHMe
)i(}i,llKo<t>aJttoe cneKamte - cneKattHe no powKoooro Tena npH TeMnepazype, o6ec net.tHBatomeH: IlOl!BJieHHe JKH,llKOH <t>aJbl
15.1. 06U,\af1 xapaKTepMCTMKa cneKaHMH
CneKaHHe c yqacTHeM)l(H,lJ,KOH ct>aJhIHMeeT lllHpoKoe TeXHuqec Koe npHMeHeHHe npH npOH3BO,lJ,CTBe pa3JIH1IHh X THTIOB nopOlllKOBhlX KOMTI03HUHOHHhlX MarepHaJIOB. TipHMepaMH CHCTeM, cneKaHHe·KOTO pbIX npoucxo.n.HT c yqacTHeM)l(H,lJ,KOH ct>aJh, MOryT cJITh Cu-Sn (227 °C), Fe-Cu (1083 °C), Fe-P (1050 °C), Cu-Pb (326 °C), Cu Bi (270 °C), Cu-Cd (314 °C), W-Cu (1083 °C), W-Ag (961 °C), Mo-Cu (1083 °C), Mo-Ag (961 °C), Cr3C2-Ni (1200 °C), WC-Co (1340 °C), TiC-Ni (1280 °C) H MHOrHe.n.pyrue (B CK06Kax yKa3aHbl TeMnepaTypbl B03MO)l(ff0f0 TIO.SIBJieHH.SI)l(H,lJ,KOH ct>aJbl B pe3yJihTare TIJiaBJieHH.SI JiefKOTIJiaBKOH KOMTIOHeHThl HJIH CTpyICTypHOH COCTaB JI.SIIOIUeH, o6pa3yioIUeHC.SI cornacHO COOTBeTCTBYIOIUeH.uuarpaMMe co CTO.SIHH.SI). TepMO.UHHaMuqecKHM ycJIOBHeM 3cPcPeKTHBHoro)l(H,lJ,Koct>aJHoro cneKaHH.SI.SIBJI.SleTC.SI CTpeMJieHHe MHOfOKOMilOHeHTHOH CHCTeMbl K MHHHMYMY CB060,lJ,HOH noBepXHOCTHOH 3HeprHH H XHMHqecKoro no TeHUHaJia, KaK H npu TBep.n.oct>aJHOM cneKaHHH. Ho B ornuque oT TBep.n.oct>aJHOfO npH)l(H,lJ,KOcPa3HOM cneKaHHH H3-3a 60JibllleH no.n. BH)l(HOCTH CHCTeMbl)l(H,lJ,KOe-TBep.n.oe 6oJiee HafJI.Sl,lJ,HO npO.SIBJI.SleTC.SI .n.eH:CTBHe OCHOBHh X.ll.B·IUHX CHJI o6beMHOfO YTIJIOTHeHH.SI nopolll KOBOfO reJia - CHJI KanHJIJI.SlpHoro CT.SlfHBaHH.SI. B npucyrCTBHH)l(H,lJ, KOH ct>aJhI npu onpe.n.eJieHHh X ycJIOBH.SIX o6JieNaeTc.st pa3BHTHe CHJI cueTIJieHH.SI Me)l(,lJ,y OT,lJ,eJibHhlMH qacTHUaMH nopOlllKa H MO)l(eT cct>op MHpOBaTbC.SI MaJIOnopHCTa.SI (Il «1%) CTpyKrypa.IlpH)l(H,lJ,KOcPa3- HOM cneKaHHH B nopolllKOBOM TeJie B03HHKaeT CBOero po.n.a KanHJI JI.SlpHa.SI CHCTeMa (pa3Mepbl qaCTHU nopolllKa COH3MepHMhl c none peqHblMH pa3MepaMH nopOBh X KaHaJIOB), COCTO.SIIUa.SI H3 TBep.n.oH:, )l(H,lJ,KOH H ra3006pa3HOH ct>aJ. B CB.Sl3H c 3THM 60Jih11Joe 3HaqeHHe npu o6perneT CMaqHBaHHe TBep,lJ,b X qaCTHU)l(H,lJ,KOH ct>aJOH, Mepofl: KOTO poro.stBJI.steTc.st BeJiuquHa KpaeBoro yrna cMaquBaHH.SI 3 (puc. 256):
8 - 5582
r.ue aT, a)I(, aT_lK - COOTBeTCTBeHHO noBepXHOCTHbi e 3Heprn:H Ha rpa HHUaX pa3,UeJia TBep.uoe TeJIO- raJ,)J(fl,llKOCTb- ra3 H TBep.uoe TeJIO )J(fl,llKOCTb. Pa6orn a.ureJHH HJIH pa6oTa OTpbIBa)J(fl,llKoi1 KanJIH oT TBep .uoi1 noBepXHOCTH BblpIDKaeTCH <t>opMyJIOH
(15.2) TepMO.UHHaMw-1ecKHM ycJioBHeM cMalfHBaHHH HBJIHeTCH yMeHbllleHHe CBOOO,llHOH 3HeprnH CHCTeMbl npH npeBpalll,eHHH rpaHHU pa3,lleJia TBep .uoe TeJio-raJ H)l(H,llKOCTb-raJ B rpaHHUY paJ,UeJia TBep.uoe TeJio )l(H,llKOCTb, T.e. pa6orn a.ureJHH,llOJI)l(Ha 6bITb noJIO)l(HTeJibHa. npH nOJIHOM CMalfHBaHHH S = 0°, npH nOJIHOM HeCMalfHBaHHH s = 180°, npH 0 < s < 90° CMalfHBaHHe ClfHTalOT xopollIHM, a npH s 90° CMalfHBaHHe nJioxoe H o6pa3oBaBlllaHCH)l(H,UKaH Q>a3a TOpMo- 3HT cneKaHHe, npenHTCTBYH ynJIOTHeHHIO nopolllKOBOro TeJia. CMalfHBaHHe YJIYlflllaeTCH (yroJI S yMeHblllaeTCH) npH yMeHbllle HHH a,_)I((HanpHMep, npH HaJIHlfHH B KOHTaKTHpYJOlll,HX Q>aJax noBepx HOCTHO-aKTHBHbIX Belll,eCTB HJIH npH HJMeHeHHH TeMneparypb!). 1'b MeHeHHe BeJIHlfHHbl aT_lK MO)l(eT TaK)l(e 6b!Tb CJie,UCTBHeM H3MeHeHHH BeJIHlfHH a H a (3KcnepuMeHTaJibHO ycTaHoBJieHo, lfTO c pocToM a T lK T pacTeT H aT_,., HO B 60Jiblllei1 CTeneHH, B peJyJibTaTe KpaeBOH yroJI yBeJIHlfHBaeTCH). npH yBeJIHlfeHHH BpeMeHH KOHTaKTa)l(H,UKOe-TBep,UOe H TeMne parypbl KpaeBoi1 yroJI yMeHblllaeTCH H cMalfHBaHHe YJIYlfUJaeTCH. B paM Kax TepMO,llHHaMHlfeCKOtt TeopHH CMalfHBaHHH, OCHOBaHHOH Ha cy lll,eCTBOBaHHH XHMHlfeCKoro B3aHMO,lleHCTBHH Ha Me)l(Q>a3HOH rpaHH ue TBep,lloe TeJio-)l(H,llKOCTb, 3TO o6bHCHHeTCH ycJioBHHMH npoxo)l( .L I.eHHH XHMHlfeCKOH peaKUHH Ha 3TOH rpaHHUe. noBbIUJeHHe TeMnepa TYPbInpHBO,llHT K yMeHbllleHHIO CBo6o.uHoi1 3HeprnH CHCTeMbIH yMeHb UJeHHIO BeJIHlfHHbl a,_,., a BJIHHHHe BpeMeHH CBH33HO c npo,llOJI)l(H TeJibHOCTbIO ycTaHOBJieHHH paB HOBeCHH npH XHMHlfeCKOM B33H MO,UeHCTBHH Q>aJ. BeJIHlfHHa KpaeBoro yrna cMa lfHBaHHH 33BHCHT OT OKpy:>KaIO
pb!X CHCTeM. OTMeTHM tteKOTOph1e JaKoHoMepHOCTH, xapaKTepHbi e,ll,JIH cneKa HHH B npHCYTCTBHH)J(H,llKOH Q>aJbJ: 1. 06pa30BaHHe)J(fl,llKOH Q>a3bl npH cneKaHHH, KaK npaBHJIO, co npOBO)l(JJ,aeTCH HHTeHCHQ>HKaU Hei1 yca,UKH, lfTO B npHHUHne noJBO JIHeT IlOJIYlfHTb cnelfeHHblH MaTepHaJI c OlfeHb Bb COKOH nJIOTHOCTblO H MaJIOH OCTaTOlfHOH nopHCTOCTbIO npH OTHOCHTeJibHO KOpOTKOM Bpe MeHH npouecca; B CBH3H c 3THM cneKaHHe B npHCYTCTBHH)l(H,llKOH Q>a3bl lfaCTO npe,UCTaBJIHeT co6oi1 aJibTepHaTHBY HCnOJib30BaHHIO Bbl COKHX,UaBJieHHH Q>opMoBaHHH HJIH 60JibllIHX TeMneparypblH,ll,JIHTeJib HOCTH BbI,llep)l(KH npH cneKaHHH,ll,JIH nOJIYlfeHHH MaTepHaJia Bb!COKOH nJIOTHOCTH.).l,JIH HeKOTOpb!X nopollIKOB 01.feHb TBep,llb X MaTepHaJIOB HJIH cnJiaBOB)J(fl,llKOQ>aJHOe cneKaHHe MO)l(eT 6b!Tb e,llHHCTBeHHO B03M0)1( Hb!M cnoco6oM noJiyqeHHH Bb!COKOH nJIOTHOCTH KOHelfHOro npon.yKTa. 2. 3Q>Q>eKT yBeJIHlfeHHH yca,llKH JaBHCHT KaK OT Q>H3HKO-XHMH lfeCKHX xapaKTepHCTHK KOMnOHeHTOB, TaK H OT KOJIHlfeCTBa)l(H,llKOH Q>a3bl, pa3Mepa lfaCTHU TyronJiaBKOH COCTaBJl·HIOlll,eH H HalfaJibHOH nopHCTOCTH 6p11KeTOB. YBeJIHlfeHHe KOJIHlfeCTBa JierKonJiaBKOH cocTaB JIHIOlll,eH cnoco6cTByeT ycan.Ke, HO npH HaJIHlfHH HeKOTOpoi1 B33HM ar->K a 6 P11c. 256. CMa'1ttBaH11e lK11!lKOCTblO rnep!lOH no11cpXHOCTtt (a) 11 MelKKp11CTaJl Jll1THOro npoMCJKyrKa (6) lll,eH 3TMocQ>epbI, CTeneHH ee OlfHCTKH, cnoco6HOCTH K o6pa- 30B3HHIO noBepXHOCTHbIX nJieHOK H.upyrnx Q>aKTOpoB. B Ta6JI. 52 npH Be,lleHbI 3HalfeHHH s,ll,JUI HeKOTO- HOH paCTBOPHMOCTH KOMnoHeHTOB HJMeHeHHe nJIOTHOCTH npH)l(HD. KoQ>aJHOM cneKaHHH MO)J(eT OCJIO)l(HHTbCH npoueccaMH reTepo n.u<t>Q>yJHH; HCnOJib30BaHHe 6oJiee MeJIKHX Q>paKUHH ryronJiaBKOH co CTaBJIHIOlll,eH cnoco6cTByeT yBeJIHlfeHHIO yca,UKH. B CBHJH co JHalfH TeJibHbIM ynJIOTHeHHeM npH cneKaHHH pOJib BeJIHlfHHbl HCXOD.HOH nopHCTOCTH, K33aJIOCb 6bl, npen.cTaBJIHeTCH He CTOJ!b B3:>KHOH, HO 3Ha- s• 227 llJITeJibHajf yca,n;Ka 6pMKeTOB c BbICOKOH HallaJibHOH rropMCTOCTblO JaT PYJlHjfeT rronyqettMe MJJleJIMH c Bb COKOH TOllHOCTbIO paJMepoB, a crre KattMe 6pMKeTOB c HMJKOH MCXOJlHOH rropMCTOCTblO MO)((eT rrpHBeCTM ]la)((e K MX poczy rrpM crreKaHMM, B CBjfJM c TeM 4TO BCJie]lCTBMe pacTe KaHMjf)((HJlKOH <f>aJbl MOryT o6paJOBbIBaTbCjf MJOJIHpOBaHHbie rropbl, ]laBJieHMe raJa B KOTopblx, KaK H B cnyqae TBepJlo<f>aJttoro crreKaHffjf, 6yJleT rrpelljfTCTBOBaTb yca,n;Ke. 3. B tteKoTopb X cnyqajfx)((HJlK <f>aJa npMCYTCTBYeT npM cneKa HMM JIMlllb B TelleHMe orpaHMlleHHOro BpeMeHM. IlpOTeKaHMe npouec COB peaKTMBHOH JlM<l><f>YJMM npMBOJlMT K o6pa30BaHMIO JlPYfMX 6onee zyroIIJiaBKHX <f>a3 HJIM K pacTBopeHMIO)((HJlKOH <f>aJbl B TBepJlOH, M cneKaHMe OCYllJeCTBJijfeTCjf B OCHOBHOM B TBepJlOH <f>aJe. 4. Tipouecc)((HJlKo<f>aJttoro cneKaHJljf qacrn npHBOJlMT K nonyqe HHIO MeTaJIJIHlleCKHX CTpYKTYP, o6na,n;aIOIUHX oco6eHHb MM MexaHM qecKMMM CBOHCTBaMH; eCJIM Ta <f>aJa, KOTopajf BO BpeMjf cneKaHMjf 6bIJia)((HJlKOH, coxpattjfeT CBOM oco6eHHOCTM B cneqeHHOM MaTepMa Jie, TO Otta OlleHb llaCTO npH]laeT eMy YHMKaJibHbie CBOHCTBa. B caMoM o6IUeM cnyqae)((HJlKHe MeTaJIJibIxoporno cMallMBaIOT (Kpa eBoii yroJI CMallMBaHMji o6bl4HO He npeBbilllaeT 30-40° M qacTO Ha- 6JIIO]laeTCji IIOJIHoe CMallMBaHMe) llMCTb e MeTaJIJIHlleCKHe IIOBepXHOCTM M IIOBepXHOCTM Tex HeMeTaJIJIMlleCKHX HJIM MeTaJIJIOIIO]l06Hb X KOMIIO HeHTOB (OKCH]lOB, 6opH]lOB, Kap6H]lOB M HMTpHJlOB paJJIMllHb X Me TaJIJIOB, rpa<f>MTa M Jlp.), c KOTOpblMM OHM BczynaIOT B XMMMlleCKOe BJaMMOJleHCTBMe. TiojfBJieHMe)((HJlKOH <f>aJbInpM ttarpeBe CBjfJatto c pacIIJ1aBJ1eHMeM 6onee nerKOIIJiaBKOfO KOMIIOHeHTa HJIM CTpYKTYPHOH COCTaBJijfIOIUeH
(HanpMMep, 3BTeKTMKH) cneKaeMoro MaTepMaJia, a TaK)((e c «KOHTaKT Hb M» IIJiaBJieHMeM, KOfJla)((HJlK <f>aJa BOJHMKaeT npM TeMnepazype 6onee HMJKOH, qeM TeMnepazypa IIJiaBJieHMjf yKaJaHHblX COCTaBJijflO IUHX nopollIKOBOfO Tena. IlpM 3TOM MexaHM3M cneKaHMjf c yqacTHeM )((HJlKOH <f>aJblJaBMCMT OT xapaKTepa ]lMarpaMMblCOCTOjfHlrn COOTBeT CTBYJOIUeH CMCTeMblKOMIIOHeHTOB. l.JeM nyqrne CMallHBaHMe, TeM 66Jib llIMe KOJIMllecrna)((HJlKOH <f>aJbIMoryr YJlep)((MBaTbCjf B nopornKOBOM TeJie BO BpeMjf cneKaHMjf, He BbITeKajf M He MCKa)((ajf ero <f>opMy. B npMcyrcTBMM)((HJlKOH <f>aJbIcymecTBeHHo yBeJIHll MBaeTCjf cKo pocTb caMo- M reTepOJlH<l>YJHM aTOMOB, llTO ycKopjfeT cIIJ1aB006pa JOBaHMe, M o6nerqaeTCjf nepeMeIUeHHe TBep]lbIX llaCTHU OTHOCMTeJib HO Jlpyr Jlpyra, cnoco6cTByjf JanonHeHMIO nop BemecTBoM. B CBjfJH c 3TMM npH')((HJlKo<f>aJHOM cneKaHMM MO)((HO o6ecne4HTb IIOJiyqeHMe npaKTMlleCKH 6ecnopMCTblX nopOIIIKOBblX HJJleJIMH (MaTepHaJIOB). PaJJIMllaIOT cneKaHMe nopornKoBoro Tena c npucyrcTBHeM)((HJl-
228 KOH <f>aJblJlO KOHUa M30TepMM4eCKOH Bb Jlep)((KM H c ee HClleJHOBC HMeM BCKOpe IIOCJie IIOjfBJieHHjf (XOTjf HarpeB npO]lOJI)((aeTCjf), a TaK )((e cneuM$M4eCKYIO pa3HOBHJlHOCTb nepBOfO THIIa npouecca)((MJlKO <f>aJHOfO cneKaHMjf, KOTopyIO HaJbIBaIOT MH$HJibTpauueM: nopOIIIKO BOH <f>opMOBKH. CTaAMM cneKaHMR B 1938 r. 3apy6e)((Hb1e MCCJie]loBaTeJIM IlpaH:c, CMMTeJic H BHJibjiMC c<f>opMyJIMpoBaJIM npeJlCTaBJieHMe 06 yIIJIOTHCHHM npM)((HJlKo<f>aJHOM CIICKaHMM KaK CJieJlCTBMe ]lByx rrOCJieJlOBaTeJibHbIX CTa,D;HH. Ilo MX MHe HMIO, npM IIOjfBJieHMM)((HJlKOH <f>aJblCHaqaJia (nepBajf CTa,ll;Mjf) TBep ]lble qaCTHUbl nepeMeIUaIOTCji JlO COCTOjfHMjf IIJIOTHOH YKJia,ll;KM IIOJl BJIMjiHMeM CMJI IIOBepXHOCTHOro HaTjf)((CHMjf CMallMBaIOIUeH HX)((HJl KOCTM; qaCTMUbl CMeIUaIOTCjf OTHOCHTeJlbHO JlPYf Jlpyra 6JiafOJlapji BOJHMKHOBeHMIO OTpHUaTeJibHOfO KaIIMJIJijipHOfO JlaBJieHMjf B)((H]lKO CTHbIX «MOCTMKaX» (MaH)((eTax), COeJlMHjfJOIUMX 3TM qaCTMUbl. IlocJie JaBeprneHMjf nepHOJla cBo60JlHOro rrepeMeIUeHMjf qacTMU JlaJibHeM:rnee YIIJIOTHCHMe (BTOpajf CTa,ll;Mjf) npOHCXOJlMT 6nar0Jlapj1 HX nepeKpHC TaJIJIMJaUMM qepe3)((HJlKYIO <f>aJy (06jfJaTeJibHOe ycJIOBHe KOTOpoH: - HaJIMllMe paCTBOpHMOCTM TBep]lOH <f>aJbl B)((HJlKOCTH). 0JlHaKO cpaJy )((e BOJHMKJIM COMHeHMjf H 6bIJIM orry6JIMKOBaHbl BbICKaJbJBaHHjf He KOTOpblX MCCJieJlOBaTeJieH (HanpMMep,)l)KoHCOHa B 1938 r.), CBjfJaHO JIM yIIJIOTHeHMe c pocTOM qacTHU B CBjfJH c MexaHMJMOM nepeKpMc- Til.TIJIMJaUHM. B 1953 r. KeHHOH H JleHen yKaJaJIH eme Ha OJlHH MexaHHJM, npu- BOMIUHH K ynnoTHeHHIO npM)((HJlKo<f>aJHOM cneKaHMH: Ha JaKJIIOllH TeJibHOH CTa,D;HH cneKaHHjf B npouecce JaBeprneHHjf nepeKpHCTaJIJIM JaUHH (npM HaJIHllHH paCTBOpMMOCTH TBepJlOH <f>aJbl B)((HJlKOCTH) HJIM cpa3y nocJie JaBeprneHHjf nepBOH CTa,D;HH (npH OTCYTCTBHH pa CTBOpHMOCTH TBCPJlOH <f>aJbl B)((HJlKOCTH) pa3BHBaeTC}I npouecc cpa CTaHHjf qacTHU zyronJiaBKOro KOMIIOHeHTa B)((eCTKHH KapKaC («CKe JieT»). 0HH TaK)((e OTMeTHJIH, 4TO ynJIOTHeHHe npH nepeKpHCTaJIJIHJa
K JlpyroH. OTMeTHM, 4TO y)l(e nollTH II}ITbJleC}IT neT TeopeTHlleCKHe pa3pa- 60TKH no)((HJlKo<f>aJHOMY cneKaHHIO 6aJHpyIOTC}I Ha YKaJaHHbIX Bbtrne npeJlCTaBJieHHjfX 0 Tpex B03MO)l(HblX MeXaHHJMaX ynJIOTHeHH}I, pa3BH BaIOIUHXC}I c IIO}IBJieHHeM)l(HJlKOH <f>aJbl nocJieJlOBaTeJibHO npH qac- I 229 rn:qHOM Ha.JIO)KeHHH (pHC. 257):)l(H)J,KOe TeqeHHe (neperpynnHpOBKa), pacTBopeHHe-ocIDK,l(eHHe (nepeKpHCTa.JIJIHJau m1), cpacTaHHe qacTHl.l TYfOruiaBKOH <l>aJhI(o6paJoBaHHe)KeCTKoro KapKaca HJIH «CKeJieTa»). KirneTHKa 3THX npoueccoe cyll.lecTBeHHo JaBHCHT OT cTeneHH OJJ.Ho POJJ.HOCTH CMeCH KOMilOHeHTOB, Haqa.JibHOH nopHCTOCTH nopOlllKO BOfO rena, KOJIHqecTBa o6pa3)'10ll.leHCH)KH)J.KOH <t>aJbl, JIHHeHHOfO paJMepa nopOlllHHOK, xapaKTepa CMaqHBaHHH TBep)J.OH <t>aJbl)l(H)J,KO CTblO, BJaHMHOH paCTBOpHMOCTH <t>aJ H)J.OCTaTOqHo 60JiblllOfO KOJIH
qecTBa JJ.PYrHX <t>aKTOpOB. PaccMOTpHM Ka)K)J.YJO HJ YKaJaHHh X CTaJJ.HH yruIOTHeHHH. llep60Jl cmaiJUR. Ee o6blqHo HaJblBaIOT npou,eccoM nepe2pynnupo6KU (JJ.OCTaToqHo qacro B KaqecTBe CHHOHHMa fOBOPHT 0 MexaHU'leCKOU nepe2pynnupooKe). loHBHBlllaHCH)KH)J.KaH <l>aJa JanOJIHHeT JaJopbl Me)K)J.y TBep)J.blMH qacTHl.laMH H, HrpaH pOJib)l(H)J,KOH CMaJKH, o6nerqaeT BJa HMHOe nepeMell.leHHe qacTHl.l, npHBOJJ.Hll.lee K yruioTHeHHIO nopolll Koooro TeJia. TaKoe nepeMell.leHHe qacTHl.l, conpoeo)K)J.aIOll.leecH YMeHh llleHHeM ceo6oJJ.HOH noeepxHocTH)l(H)J,KOCTH, npoHCXOJJ.HT noJJ. BJIHH HHeM)J.aBJieHHH, o6ycJioBJieHHOfO KPHBH3HOH noeepXHOCTH B03HHKa IOll.lei"i)l(H)J,KOCTHOH «MaH)KeTbl» (T.e. noeepXHOCTH paJ)J.eJia)l(H)J,KOCTb raJ), o6paJyeMoH: o6'beMOM pacruiaea, JaKJIIOqeHHoro Me)K)J.y CMe)K Hh MH qaCTHl.laMH (nopolllHHKaMH).
80,lJ.HlllYIO K MaKCHMa.JlhHOMY JHaqeHHIO OTpHl.laTeJibHOfO KanHJIJIHp Horo,lJ.aBJieHHH B)KH)J.KOCTH H CHJibl, C)KHMaIOll.leH TBep)J.ble qacTHl.lhl. Ilpu yxy,lJ.llleHHH cMaqueaHHH KPHBHJHa eomyroii noeepXHOCTH «MaH )KeTh» yMeHblllaeTCH, KanHJIJIHpHbie CHJihly6bIBalOT H npH s > 65 - 85° (B JaBHCHMOCTH OT KOJJHqecTBa)KH)J.KOCTH H reoMeTpHH KOHTaKTa Me)K)J.y TBep)J.blMH qacTHl.laMH) noeepXHOCTb)l(H)J,KOCTHOH «MaH)KeTbl» CTaHOBHTCH BhinYKJIOH, 3HaK KanHJIJIHpttoro)J.aBJieHHH MeHHeTCH H BMeCTO CTHrHBaHHH TBep)J.blX qaCTHl.l noHBJIHeTCH CHJia, CTpeMHll.laHCH HX pa3)J.BHHYTh (Ta6JI. 53). IlpH nJIOXOM cMaqueaHHH «Matt)KeTa» MO)KeT He o6pa30BaThCH, a 6y)J.eT npoHCXO)J.HTb CTHrHBaHHe)KH)J.KOCTH B Kan JIH Ha noeepXHOCTH qaCTHl.l TBep)J.OH <t>aJbl. ECJIH noHBJIHIOIIlaHCH)l(H)J,KaH <t>aJa pacnpeJJ.eneHa B o6'beMe nopolll Koeoro rena paBHOMepHO, TO B03HHKalOll.lHe KanHJIJIHpHble CHJibl no BJIHHHHIO Ha npouecc neperpynnHpOBKH 3KBHBa.JieHTHbl,lJ.eHCTBHIO )J.aBJieHHH eceCTOpOHHefO C)KaTHH. ,ll,Jrn o6pa30BaHHH)l(H)J,KHX npocJioeK B npHKOHTaKTHOH o6JiaCTH Me)K)J.y TBep)J.blMH qacruuaMH He06XO)J.HMO, qTo6bl 3HepreTHqecKH 6hIJIO uenecoo6pa3HO HX pa3)J.eJieHHe noHBJIHIOll.leHCH)KH)J.KOCThlO, TaK KaK 6e3 pa3pbIBa Me)KqacTHqHb X KOHTaKTOB, B03HHKI1IHX B nopOlllKOBOM rene)J.0 nOHBJieHHH)l(H)J,KOH <t>aJhl, HeB03MO)KH0 CB060)J.HOe nepeMe ll.leHHe qacTHl.l, c KOTOpbIM HenocpeJJ.CTBeHHO CBH3aH npouecc HX neperpynnHpOBKH u eoJpacTaHHe ruIOTHOCTH ynaKoBKH. Cq11raeTcH, qTO c Il03Hl.lHH TepMO)J.HHaMHKH ycJIOBHeM TaKOfO pa3be)J.HHeHHH qa I CTHl.l noHBHBllleHCH)KH)J.KOH <t>aJOH HBJIHeTCH COOTHOllleHHe OTHOCHTeJibHO roqKH Me)Kqa CTHqHoro KOHTaKTa. BMecre c a. 2a cos ('¥/2), (15.3)
PHc. 257. KHtteTWiecKfill KpHBW! yCll,ll,KH rrpH lKH,!lK<><l>aJHOM crreKaHHH: 1 - lKH,!lKoe reqe HHe; 2 - pacTBopeHHe H oca)l(JleHHe; 3 - Tsep.u<><t>aJHoe crreKaHHe noeopoTOM qaCTHl.l npOHCXO )J.HT nepeMell.leHHe o6beMa )l(H)J,KOCTH, H o6JiaCTb OTpHl.la TeJibHOfO KanHJIJIHpHOfO)J.aB JieHHH pacnpOCTpaHHeTCH Ha HOBble yqaCTKH noeepXHOCTH TBepJJ.hIX qacTHU, ycKopHH HX noeopoT H BJaHMHb H C)J.BHr. IlpH IlOJIHOM CMaqHBaHHH no BepXHOCTb «MaH)KeTbl» HMeeT HaH60JlblllYJO KPHBH3tty, npH- I r)J.e a. - noeepXHOCTHaH 3HeprHH Ha Me)KqacTHqHOH rpaHHl.le; '¥ - rp
T a 6 JI " 1..1, a 53. Jlaueiiuuyca,iuat M/ I (%) a cacTeMe W-Cu a lllBHCH MOCTH"OT o6i.eMa lKll)J.KOH cl»a:Jw, ttpaeaoro yrJia CMa'lllBaHJIH H Hcxo,nuoii
KpaesoH yron CMaqHBaHHll, rpa.u
I KamuurnpHble CHJibl, C)((JfMaIOIUHe CMe)l(Hb e TBep,llbie qacTHUbl, coe,llHHeHHble He KOTOpb M OObeMOM)((Jf,llKOCTH, HMeIOT o6mee IIpOHCXO)l(JleHHe c CHJIOH, IIO,llHHMaIO IUeil: lKH,!lKOCTb B CTeKIDIHHOM KalIHJIJUlpe; HX BeJJHqHHa MO)l(eT.llOCTHraTb HeCKOJibKHX MerarracKaJieil:. I 231 ,ll,ByrpaHHbIH (.n.Hre,ll,pa.JibHbIH) yroJI, paBHblH '¥ = q>o +23 (% - yroJI Me)J{,lly KaCaTeJibHbIMH K noeepXHOCTH ":laCTHU B MeCTe HX conpHKOC HOBeHH.ff). BbipIDKeHHe (15.3) BbinOJIH.ffeTC.ff npH JII06bIX JHa":leHH.ffX
cooTHoweHHe (15.3) o6bI":IHO He BhmoJIH.ffeTC.ff. B pea.JibHbIX nopow- KOBbIX Tenax, xapaKTepHJYIOIUHXC.ff,lJ,OCTaTO":IHO Ma.JIOH eeJIH":IHHOH Me Ta.JIJIH":leCKHX KOHTaKTOB Me)J{,lly 1:1aCTHUaMH H Ha.JIH":IHeM Jarp.ff3HeHHH Ha HHX, BeJIH":IHHa a.rp cymecTBeHHO BOJpacTaeT, H COJ,lJ,aIOTC.ff 6oJiee 6JiaronpH.ffTHbie yCJIOBH.ff,ll,Jl.ff BbJnOJIHeHH.ff COOTHOWeHH.ff (15.3). npH Ha.JlfflIHH paCTBOpHMOCTH rnep.n.oii cf>aJbl B)((H,ll,KOH yCJIOBHe (15.3)
Bmopaa cmaiJuR. 0Ha onpe.n.e- i:,,;3.:.:._, JI.ffeTC.ff npoTeKaHHeM npouecca nepeKpHCTa.JIJIHJaUHH qepe3)((H,ll,- 9 KYIO cf>aJy H ee o6bl":IHO HaJbJBa- IOT pacm6opeHue-oca:J1CiJeHue \ 7 (HHor.n.a 3TOT npouecc HaJbIBa- \ JOT XUMUiteCICOU nepezpynnup06KOU). / '\\ CymecrneHHYIO poJib 3TOT npo- 5 / / \ \ uecc MO)((eT 11rpaTh JIHWh B cHc- / // \:\ ·TeMax, r.n.e TBep.n.a» cf>aJa HMeeT 3 L- ---'-.-1..--.. - - - ,ll,Jl.ff MHOfHX TeXHH":leCKH Ba)((HbJX KOMnOJHUHH BbJnOJIH.ffeTC.ff; paCTBO peHHe B nopOWKOBOM TeJie npeHMYIUeCTBeHHO H,lJ,eT B,lJ,OJlb Me)((JepeH HeKoTopyIO paCTBOpHMOCTb B 0 )((H,ll,KOH. 20 40 (j() 80 )/(uOKoR l/Ja30, % (OOoeMH.) 100 HblX rpaHHU H paCTBOp.ffIOIUa.ff)((H,lJ,KOCTb paJo6maeT TBep,ll,ble 1:1aCTHUbl. OrMeTHM, ":ITO 1:1eM HH)((e HCXO,ll,Ha.ff nJIOTHOCTb nopowKoeoro TeJia, TeM MeHbWe eepO.ffTHOCTb o6paJOBaHH.ff B HeM npO":IHOro)((eCTKOro KapKaca Ha Ha":la.JibHOH CTa,ll,HH cneKaHH.ff H TeM ner1:1e H,lJ,eT npouecc neperpynnHpOBKH ":laCTHU. npH OTHOCHTeJibHO OOJiblUOM CO,ll,ep)((aHHH JiefKOJl.JiaBKOfO KOMnO nocKOJlbKY paCTBOpHMOCTb rnep.n.oro eemecTea B)((H,ll,KOCTH yeeJIHlJHBaeTC.ff c yeeJIHlfeHHeM KpHBHJHbI(c YMeHhWeHHeM paJ Mepa 1:1acTHU rnep.n.oft: cf>aJhI), MeJIKHe 1:1acTHUbl paCTBOp.ffIOTC.ff Pttc. 258. KpHBbie JIHtteiittoii.yca,uKH & npeccosoK HJ nopoUIKa cnnasa cHCTeMbI W-Ag B JaBHCHMOCTH oT o6beMttoro co.aep.lKaHHR)((H,llKOH Q>a3bl npH 1300 'C: 1 - HHQ>HJ!bTP3UHR; 2 - cneKaHHe HeHTa [10-30 % (o6beMH.)], Ma.JIOM paJMepe lJaCTHU rnep,ll,OH cf>aJblH n.o crnTO":IHO BbICOKOH TeMnepazype cneKaHH.ff npouecc neperpyn nHpoeKH lJaCTHU c HX nepeMeIUeHHeM,ll,O COCTO.ffHH.ff nJIOTHOH yna KOBKH COCTaBJI.ffeT OCHOBHOH MeXaHHJM YJl.JIOTHeHH.ff. nocJie ero Ja eepweHH.ff npOCTpaHCTBO Me)J{,lly TBep,ll,blMH lJaCTHUaMH OKaJbIBaeTC.ff nO'ITH noJIHOCTblO JanoJIHeHHblM)((H,ll,KOH cf>aJOH. OrMeTHM, 'ITO B 60JibWHHCTBe cny1:1aee neperpynnHpoeKa 1:1aCTHU He o6ecnelfHBaeT JaBepweHH.ff ynJIOTHeHH.ff H nocJie ee OKOHlJaHH.ff npocTpaHCTBO Me)(( .ll.Y TBep,ll,bIMH 1:1aCTHUaMH JanOJIHeHo He TOJlbKO)((H,lJ,KOCTbIO, HO H nopaMH. B o6meM CJ1y1:1ae Ha 3TOH CTa,ll,HH YJl.JIOTHeH H.ff BeJIHlJHHa OTHOCH TeJibHOH o6beMHOH yca.n.KH nopowKoeoro Tena AV/ V npH6JIH)((eHHo onHcbIBaeTC.ff JaKOHOM AV/ V - •k (k > 1). BKJia.n. npouecca MexaHHlJec KOH neperpynnHpOBKH B o6my10 OObeMHyIO yca.n.J<Y cneKaeMoro nopow Koeoro TeJia yeeJIHlJHBaeTC.ff c poCTOM KOJIHlJeCTBa)((H,ll,KOH cf>aJbl H yMeHbWeHHeM paJMepa lJaCTHU zyronnaBKOH cf>aJbl, TaK KaK npH 3TOM yMeHbWaeTC.ff eepO.ffTHOCTb JaKJIHHHBaHH.ff TBep,ll,bIX qaCTHU npH HX BJaHMonepeMeIUeHHH. C1:1HTaIOT, 1:1To nonHoe yJl.JioTtteHHe B peJyJihTaTe TOJibKo o.n.ttoro npouecca neperpynnHpOBKH MO)((eT 6bITh nonyqeHo npH co.n.ep)((aHHH )((H,ll,KOH cf>aJbl 35-50 % (o6beMH.) (pHC. 258).)],JI.ff CHCTeM c HeBJaH MO,lJ,eHCTBYIOIUHMH KOMnoHeHTaMH 3TOT npouecc,ll,Jl.ff ynJIOTHeHH.ff nopoWKOBOfO Tena.ffBJI.ffeTC.ff OCHOBHbIM. H HClJeJaIOT, B TO epeM.ff KaK KpynHb e paCTYT, npHHHMa.ff 6onee npa BHJlbHYIO cf>opMy (HanpHMep, OKpyrnyIO HJIH orpaHeHHYIO), o6ecne lJHBaIOIUYIO MHHHMHJHpoBaHHe noeepxHOCTHOH 3HeprnH. TpaHcnopT MaTepHa.Jia npoHCXO,lJ,HT nyTeM 6bICTpOH.ll.H<l>cf>YJHH 1:1epe3)((H,ll,KYJO cf>aJy. BoJMO)((HO, 1:1To 3TOT npouecc ttenocpe.n.crneHHO He npHBO.lJ.HT K yca.n. Ke, O,lJ,HaKO cnoco6CTByeT eii,noJBOJl.ff.ff qaCTHUaM Jief":le nepeMeIUaTbC.ff 8 npouecce B.ffJKoro Te":leHH.ff)((H,ll,KOCTH Ha nepeoii CTa,ll,HH cneKaHH.ff. 0.n.HaKo cymecTeyeT MHeHHe, 'ITO MexaHHJM pacrnopeHHe-oca)J{,lle HHe enp.HMYIO npHBO,ll,HT K yca.n.Ke: B peJyJibTaTe nepeoH CTa,lJ,HH cne KaHH.ff lJaCTHUbl zyronnaBKOH cocTaBJI.ffIOIUeH OKaJbIBaIOTC.ff OT,lJ,eJieHbl n.p yr OT.n.pyra TOHKHMH npOCJIOHKaMH)((H,ll,KOH cf>aJblH KanHJIJl.HpHoe .n.aeJieHHe B 3TOM cnyqae ·ypaBHOBellrnBaeTC.ff Hanp.ff)((eHH.ffMH C)((aTH.ff B JOHe KOHTaKTa. Hanp.ff)((eHHOe COCTO.ffHHe KOHTaKTOB o6ycJIOBJIHBaeT
npouecc nepeKpHCTa.JIJIH3aUHH BKJIIOlJaeT He Mettee TpeX 3JieMeH TapHblX npoueccoe: 1) pacrnopeHHe aemecrna MeJIKHX qaCTHU, T.e. nepexo.n. aTOMOB c noeepxHoCTH 3THX qacTHU B pacrnop (npouecc, qacTO HaJbJBaeMblH peaKuHeH Ha Me)((cf>a3HOH noaepXHOCTH); 2).lJ.Hcf>-
<l>Y3HIO pacTBopeHHh X aTOMOB B)l(H,l(KOCTH Me)l()J.y IlOBepXHOCT51.MH MeJIKHX H KpynHhlX qacTHU; 3) OTJIO)KeHHe pacTBopeHHOfO Bern.ecTBa Ha noBepxttoCTH KpynHh X qacrHu. PocT JepeH no 3TOMY MexaHH3MY npH)l(H,l(Ko$a3HOM cneKaHHH no;::i;qHm1eTCH TOH)Ke epeMeHHOH JaBH CHMOCTH, qTQ H pocT 3epHa npH co6HpareJihHOH peKpHCTaJIJIH3aU HH. B o6rn.eM BH,Ue HHH. J.13 Bh pa)f(eHHH (15.5) CJie,UyeT, qTO,UJIH IlOJiyqeHHH yca,UKH 3a ,UaHHOH eeJIHqHHhlnpH MaJIOH paCTBOpHMOCTH TBep,UOH <t>a3hlB)l(H,Zl KOH Tpe6yeTcH JHaqnTeJihHOe KOJIHqecTBO pacilJiaBa e nopornKoeoM TeJie, Tor.ua KaK npH 3aMeTHOH paCTBOpHMOCTH MO)f(HO orpaHHqHThCH tte60JihIIIHM co.uep)l(aHHeM JiefKOilJiaBKOH.uo6aBKH. Tpembfl cmaiJUJl. Otta HBJIHeTCH 3aKJ110qnreJihHot:I H 06h1qtto ee tta- 3hIBaIOT mBepiJorjJa3HblM cneKaHueM. Ha 3TOH CTa,UHH cyw.ecTBeHHO B03- d 11 - d 11 = Kt 0 ' (15.4) pacraeT KOJIHqecTBO TBep,Uh X qacTHU, He pa3,UeJieHHh X)KH,llKOH npo r.ue d H d0 - TeKyID.aH H HaqaJihHaH cpe.umrn BeJiffqHHa 3eptta (qacTH Uh) COOTBeTCTBeHHo; 't - BpeMH cneKaHHH; K - KOHCTaHTa.IloKa3a TeJlh CTeneHH 3aBHCHT OT Toro, KaKOH 3JieMeHTapHh H aKT onpe.uemieT CKOpOCTh Bcero npouecca; HanpHMep, eCJIH 3TO nepBh H H3 YKa3aH Hh X BhlIIIe, TO n = 2, a eCJIH BTOpOH, TO n = 3. OrMeTHM, qTQ 3Haqe HHe n He Bcer;::i;a UeJIOqHCJieHHO H B HeKOTOph X CJiyqaHX OHO MO)KeT MemlThCH BO epeMeHH.IlpH MaJIOM co.uep)KaHHH)KH,ZlKOH <t>a3hlKOH TaKT Me)f(,Uy qacTHUaMH TBep,UOH <t>a3hl 3HaqHTeJihHO ycJIO)f(HHeT KH HeTHKy HX pocra. Ilpouecc ynJIOTHeHHH CBH3aH c nepeKpHCTaJIJIHJauHeH KOCBeHHO H B OTHOCHTeJihHO He60JihIIIOH creneHH, XOTH qacTo Ka)f(eTCH, qTo IlPHMaH H cyw.ecTBeHHaH CBH3h eCTh. 3aBHCHMOCTh yca;::i;KH Ha 3TOM
V/ V - a-4/3. CJIOHKOH, KOTOphle B3aHMHO npHneKaIOTCH (cpaCTalOTCH) H B IlOP_?IIl KOBOM TeJie 06pa3yeTCH)KeCTKHH «CKeJieT»; K TOMY)Ke B KaKOH-TO MOMeHT Harpeea)l(H,l(KaH <t>aJa MO)KeT ncqeJttyTh (3aKpHCTaJIJIHJOBaThCH BCJie,UCTBHe o6orarn.eHHH ee TYfOilJiaBKHM KOMilOHeHTOM HJIH paCTBO pHThCH B TYfOilJiaBKOH <t>aJe). B JII06oM H3 3THX c.rryqaeB KHHeTHKa yca;::i;KH 6y;::i;eT onpe,UeJIHThCH JaKOHOMepHOCTHMH TBep.uo<t>aJHOfO cneKaHHH, KOTOph e paCCMOTpeHhlpattee. OrMeTHM, qTo cpacTaHHe qacTHU (nopOIIIHHOK) MO)KeT 6bITh CJie,U- CTBHeM HeCKOJlhKHX MeXaHH3MOB nepeMern.eHHH Bern.ecTBa, HeKOTO phle HJ KOTOPh X npHBO,UHT K yilJIOTHeHHIO nopHCTOro nopoIIIKOBOfO TeJia, a tteK0Toph1e HeT. TaKne npouecchI, KaK.UH<t><l>YJHH qepeJ)KH,Zl KYIO <t>aJy (octtoettoii npouecc, o6ecne'IHBaIOW.HH pocT qacTHU) HJIH caMO.UH<t><l>YJHH B npHilOBepXHOCTHOM CJIOe qacTHU TBep.uoii <t>aJhl, Bh13hIBaH pocT KOHTaKTa, He npHBO,ll,HT K YMeHhIIIeHHIO o6beMa nop B cneKaeMOM nopoIIIKOBOM Telle H, COOTBeTCTBeHHO, K YilJIOTHeHHIO. pa.ueyca qacTHU l:i MexaHH3M pacTBopeHHe-oca)l()J.eHHe npaKTHqecKH oKa3h eaeTC$1 cyrn.ecTBeHHh M, KOf,Ua KOJIHqecTBO)l(H,l(KOH <t>a3hl COCTaBJI$leT 5 % (o6'beMH.). B CJiyqae MaJihIX KOJiffqeCTB)f(H)J;KOH <t>a3hl(no-BH,UHMOMY, <3-5 %), KOTOpb e He MOryT Bhl3BaTh MexaHHqeCKyIO neperpynnHpOBKY' HO o6ecneqHeaIOT HaJIHqHe XHMHqecKoii neperpynnHpOBKH, yilJIOTHeHHe nopornKoeoro reJia MO)KeT HMeTh MecTo Ja cqeT YMeHhIIIeHHH o6oeMa TYroilJiaBKoH: <t>aJhl, ceslJattttoro c pacTBopettHeM HeKoToporo o6oeMa qacTHU B)f(H,UKOH <t>aJe. A.Il. CaBHUKHH,UJIH 3Toro cJiyqasi: npe,UJIO)f(HJI aHaJIHTHqecKoe Bh pa)KeHHe,UJIH oueHKH nopHCTOCTH cneqeHHOfO nopornKoeoro TeJia: n= n - c ·c1 (I- n) TaK)Ke KaK npH TBep.uo<t>aJHOM cneKamm, ynJIOTHeHHe nocJie JaBep rneHHH neperpynnHpOBKH qaCTHU npH)l(ff,llKO<t>aJHOM cneKaHHH MO )l(eT o6ecneqHTh TOJlhKO o6beMHOe Te'leHHe eew.ecTBa qaCTHU TBep,UOH Qroh.
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Последнее изменение этой страницы: 2016-04-23; просмотров: 244; Нарушение авторского права страницы; Мы поможем в написании вашей работы! infopedia.su Все материалы представленные на сайте исключительно с целью ознакомления читателями и не преследуют коммерческих целей или нарушение авторских прав. Обратная связь - 54.234.146.26 (0.187 с.) |