xov xwm

Synthetic pob zeb diamond

Pob zeb diamond grit feem ntau yog siv los piav txog cov nplej me me (≈0.00004 hauv.) ntawm cov pob zeb hluavtaws siv los ua cov khoom tseem ceeb rau PDC cutters.Nyob rau hauv cov nqe lus ntawm cov tshuaj thiab cov khoom, manmade pob zeb diamond yog zoo tib yam rau tej pob zeb diamond.Kev ua pob zeb diamond grit koom nrog cov txheej txheem tshuaj lom neeg yooj yim: cov pa roj carbon zoo tib yam yog cua sov hauv qhov kub thiab txias.Hauv kev xyaum, txawm li cas los xij, ua pob zeb diamond yog deb ntawm qhov yooj yim.

Cov pob zeb diamond tus kheej muaj nyob rau hauv pob zeb diamond grit muaj ntau hom kev taw qhia.Qhov no ua rau cov khoom muaj zog, ntse, thiab, vim yog lub hardness ntawm cov pob zeb diamond, tsis tshua muaj hnav resistant.Nyob rau hauv qhov tseeb, cov qauv random pom nyob rau hauv bonded hluavtaws pob zeb ua tau zoo nyob rau hauv shear tshaj tej yam ntuj tso pob zeb diamonds, vim hais tias ntuj pob zeb diamond yog cubic crystals uas puas yooj yim raws li lawv orderly, crystalline ciam teb.

Pob zeb diamond grit tsis ruaj khov ntawm qhov kub siab tshaj li pob zeb diamond ntuj, txawm li cas los xij.Vim tias nws yog xim hlau catalyst daig hauv cov qauv grit muaj tus nqi siab dua ntawm thermal expansion dua li pob zeb diamond, qhov sib txawv ntawm qhov sib txawv ntawm cov pob zeb diamond-rau-pob zeb diamond bonds nyob rau hauv shear thiab, yog tias loads siab txaus, ua rau tsis ua hauj lwm.Yog tias daim ntawv cog lus tsis ua tiav, pob zeb diamond poob sai sai, yog li PDC poob nws qhov tawv thiab ntse thiab ua tsis tau zoo.Txhawm rau tiv thaiv qhov ua tsis tiav, PDC cutters yuav tsum tau txias txaus thaum lub sijhawm drilling.

Pob zeb diamond rooj

Txhawm rau tsim lub rooj pob zeb diamond, pob zeb diamond grit yog sintered nrog tungsten carbide thiab nws yog xim hlau binder los tsim cov pob zeb diamond-nplua nuj txheej.Lawv yog cov zoo li wafer nyob rau hauv cov duab, thiab lawv yuav tsum tau ua kom tuab li structurally ua tau, vim hais tias pob zeb diamond ntim nce hnav lub neej.Cov rooj pob zeb diamond zoo tshaj plaws yog ≈2 txog 4 hli, thiab kev siv thev naus laus zis yuav ua rau pob zeb diamond rooj tuab.Tungsten carbide substrates feem ntau yog ≈0.5 nyob rau hauv. siab thiab muaj tib yam cross-sectional duab thiab qhov ntev li lub pob zeb diamond rooj.Ob ntu, pob zeb diamond rooj thiab substrate, ua ib tug cutter (Fig. 4).

Kev tsim PDC rau hauv cov duab muaj txiaj ntsig rau cov cutters suav nrog kev tso pob zeb diamond grit, ua ke nrog nws cov substrate, hauv lub nkoj siab thiab tom qab ntawd sintering ntawm qhov kub thiab txias.

PDC cutters tsis tuaj yeem tso cai kom siab tshaj qhov kub ntawm 1,382 ° F [750 ° C].Cov cua kub ntau dhau ua rau hnav sai, vim tias qhov sib txawv thermal nthuav dav ntawm binder thiab pob zeb diamond nyiam ua rau cov pob zeb diamond sib tsoo pob zeb hauv cov pob zeb diamond.Bond zog ntawm lub rooj pob zeb diamond thiab tungsten carbide substrate kuj raug cuam tshuam los ntawm qhov sib txawv thermal expansion.