Raws li cov lus pom zoo, cov hlau yog cov khoom siv ruaj khov thiab tiv taus. Txawm li cas los xij, muaj cov alloys uas tuaj yeem rov qab tau lawv cov duab tom qab deformation yam tsis tau siv cov khoom siv sab nraud. Lawv kuj yog tus cwj pwm los ntawm lwm yam khoom siv lub cev thiab cov cuab yeej cuab tam uas paub qhov txawv ntawm cov khoom siv.
Qhov tseem ceeb ntawm qhov tshwm sim
Lub cim xeeb zoo ntawm cov hlau yog tias cov hlau ua ntej deformed spontaneously rov qab los ntawm cov cua sov lossis tsuas yog tom qab tshem tawm. Cov khoom txawv txawv no tau pom los ntawm cov kws tshawb fawb thaum ntxov li xyoo 1950. xyoo pua 20th Txawm li cas los xij, qhov tshwm sim no tau cuam tshuam nrog kev hloov pauv martensitic hauv cov iav siv lead ua, thaum lub sij hawm muaj kev txiav txim ntawm atoms.
Martensite hauv cov ntaub ntawv cim xeeb yog thermoelastic. Cov qauv no muaj cov muaju nyob rau hauv daim ntawv ntawm nyias daim hlau, uas yog stretched nyob rau hauv lub txheej txheej, thiab compressed nyob rau hauv lub puab sawv daws yuav. Cov "carriers" ntawm deformation yog interphase, ntxaib thiab intercrystalite ciam teb. Tom qab cua sov lub deformedalloy, sab hauv kev ntxhov siab tshwm sim, sim rov qab cov hlau rau nws qhov qub.
Qhov xwm txheej ntawm kev rov qab los yog nyob ntawm cov txheej txheem ntawm kev raug cuam tshuam dhau los thiab qhov kub thiab txias nyob rau hauv uas nws tau ua. Qhov kev txaus siab tshaj plaws yog ntau yam cyclicity, uas tuaj yeem ua rau ntau lab deformations.
Hlau thiab alloys nrog lub cim xeeb zoo muaj lwm yam khoom tshwj xeeb - tsis yog-linear dependence ntawm lub cev thiab txhua yam yam ntxwv ntawm cov khoom ntawm qhov kub thiab txias.
Ntau yam
Cov txheej txheem saum toj no tuaj yeem ua ntau hom:
- superplasticity (superelasticity), nyob rau hauv uas cov qauv siv lead ua ntawm cov hlau tuaj yeem tiv taus deformations uas ua rau muaj zog tshaj qhov tawm los ntawm lub xeev ib txwm;
- ib leeg thiab rov qab lub cim xeeb (hauv qhov kawg, cov txiaj ntsig tau rov ua dua thaum lub caij sov);
- rau pem hauv ntej thiab thim rov qab hloov pauv ductility (sau ntawm cov kab mob thaum lub caij txias thiab cua sov, feem, thaum dhau los ntawm kev hloov pauv martensitic);
- reversible nco: thaum rhuab, thawj ib tug deformation yog rov qab, thiab ces, nrog ib tug ntxiv nce nyob rau hauv kub, lwm yam;
- kev hloov pauv hloov pauv (sau ntawm deformations tom qab tshem tawm ntawm lub nra);
- pseudoelasticity - rov qab los ntawm inelastic deformations los ntawm elastic muaj nuj nqis nyob rau hauv thaj tsam ntawm 1-30%.
Rov qab mus rau lub xeev qub rau cov hlau nrog cov nyhuvlub cim xeeb tuaj yeem mob siab heev uas nws tsis tuaj yeem cuam tshuam los ntawm lub zog ze ntawm lub zog tensile.
khoom
Ntawm cov alloys nrog cov khoom zoo li no, feem ntau yog titanium-nickel (49-57% Ni thiab 38-50% Ti). Lawv muaj kev ua tau zoo:
- siab zog thiab corrosion kuj;
- qhov tseem ceeb rov qab zoo;
- tus nqi loj ntawm kev ntxhov siab sab hauv thaum rov qab mus rau lub xeev thawj zaug (txog 800 MPa);
- zoo sib xws nrog cov qauv lom neeg;
- kev vibration absorption.
Ntxiv rau titanium nickelide (lossis nitinol), lwm cov hlau tseem siv:
- two-component - Ag-Cd, Au-Cd, Cu-Sn, Cu-Zn, In-Ni, Ni-Al, Fe-Pt, Mn-Cu;
- three-component - Cu-Al-Ni, CuZn-Si, CuZn-Al, TiNi-Fe, TiNi-Cu, TiNi-Nb, TiNi-Au, TiNi-Pd, TiNi-Pt, Fe-Mn -Si thiab lwm tus.
Alloying additives tuaj yeem hloov pauv martensitic hloov pauv kub, cuam tshuam cov khoom txo qis.
siv kev lag luam
Daim ntawv thov ntawm cov duab cim xeeb tso cai rau kev daws teeb meem ntau yam:
- tsim kom nruj cov yeeb nkab sib dhos zoo ib yam li txoj kev flaring (flanged kev sib txuas, tus kheej-tightening clips thiab couplings);
- tsim cov cuab yeej clamping, grippers, pushers;
- tsim"supersprings" thiab accumulators ntawm txhua yam zog, stepper motors;
- tsim cov pob qij txha los ntawm cov khoom sib txawv (hlau-nonmetal) lossis hauv qhov chaw nyuaj-mus txog thaum vuam lossis vuam ua tsis tau;
- tsim tawm cov khoom siv hluav taws xob rov siv tau;
- case sealing ntawm microcircuits, sockets rau lawv kev sib txuas;
- tsim cov ntsuas kub thiab ntsuas hauv ntau yam khoom siv (tshuaj tua hluav taws, fuses, lub cav cua sov thiab lwm yam).
Kev tsim cov khoom siv zoo li no rau kev lag luam chaw (tus kheej xa cov kav hlau txais xov thiab hnub ci vaj huam sib luag, cov khoom siv telescopic, cov cuab yeej rau kev teeb tsa ua haujlwm nyob rau hauv qhov chaw sab nrauv, tsav tsheb rau cov txheej txheem teb - rudders, shutters, hatches, manipulators) muaj kev cia siab zoo.. Lawv qhov zoo dua yog qhov tsis muaj impulse loads uas cuam tshuam qhov chaw nyob hauv qhov chaw.
Daim ntawv thov ntawm cov duab nco alloys hauv tshuaj
Hauv cov ntaub ntawv kho mob, cov hlau nrog cov khoom no yog siv los ua cov cuab yeej siv thev naus laus zis xws li:
- stepper motors rau stretching pob txha, straightening tus txha nraub qaum;
- lim ntshav hloov pauv;
- khoom siv kho pob txha;
- khoom siv orthopedic;
- clamps rau cov leeg thiab cov hlab ntsha;
- twj tso kua mis rau lub plawv lossis lub raum;
- stents thiab endoprostheses rau cog rau hauv cov hlab ntsha;
- tshuaj txhuam hniav rau kho hniav.
Disadvantages and prospects
Txawm hais tias nws muaj peev xwm zoo, cov duab cim xeeb muaj qhov tsis zoo uas txwv tsis pub lawv siv dav:
- khoom kim heev chemistry;
- kev tsim khoom siv thev naus laus zis, qhov xav tau siv cov cuab yeej nqus tsev (kom tsis txhob suav nrog nitrogen thiab oxygen impurities);
- phase instability;
- qis machinability ntawm hlau;
- nyuaj hauv kev ua qauv kom raug tus cwj pwm ntawm cov qauv thiab kev tsim cov alloys nrog cov yam ntxwv xav tau;
- kev laus, qaug zog thiab degradation ntawm alloys.
Ib qho kev cog lus hauv kev txhim kho thaj tsam ntawm cov thev naus laus zis no yog kev tsim cov txheej txheem los ntawm cov hlau nrog lub cim xeeb zoo, nrog rau kev tsim cov alloys raws li cov hlau. Cov qauv sib xyaw yuav tso cai rau kev sib txuas cov khoom ntawm ob lossis ntau cov ntaub ntawv hauv ib qho kev daws teeb meem.
