Graphite nrog TaC txheej

I. Txheej txheem kev tshawb nrhiav

1. TaCl5-C3H6-H2-Ar system

2. Deposition kub:

Raws li cov qauv thermodynamic, nws raug xam tias thaum qhov kub thiab txias siab dua 1273K, Gibbs dawb lub zog ntawm cov tshuaj tiv thaiv yog tsawg heev thiab cov tshuaj tiv thaiv kuj tseem ua tiav. Cov tshuaj tiv thaiv tas li KP yog qhov loj heev ntawm 1273K thiab nce nrawm nrog qhov kub thiab txias, thiab qhov kev loj hlob qeeb qeeb ntawm 1773K.

Kev cuam tshuam ntawm qhov chaw morphology ntawm txheej txheej: Thaum qhov kub tsis haum (siab dhau lossis qis dhau), qhov saum npoo nthuav tawm cov pa roj carbon monoxide dawb lossis xoob pores.

(1) Thaum qhov kub thiab txias, qhov txav ceev ntawm cov active reactant atoms los yog pab pawg yog ceev heev, uas yuav ua rau kom tsis sib xws thaum lub sij hawm tsub zuj zuj ntawm cov ntaub ntawv, thiab cov nplua nuj thiab pluag cheeb tsam yuav smoothly hloov, ua rau lub pores.

(2) Muaj qhov sib txawv ntawm cov tshuaj tiv thaiv pyrolysis ntawm alkanes thiab txo cov tshuaj tiv thaiv ntawm tantalum pentachloride. Cov pyrolysis carbon ntau dhau thiab tsis tuaj yeem ua ke nrog tantalum nyob rau lub sijhawm, ua rau saum npoo tau qhwv los ntawm carbon.

Thaum qhov kub thiab txias yog qhov tsim nyog, qhov saum npoo ntawm lubTaC txheejyog ntom.

TaCcov khoom yaj thiab sib sau ua ke nrog ib leeg, daim ntawv siv lead ua tiav, thiab cov qoob loo hloov pauv tau zoo.

3. Hydrogen piv:

Tsis tas li ntawd, muaj ntau yam cuam tshuam rau cov txheej txheem zoo:

-Substrate nto zoo

- Deposition gas teb

-Qhov degree ntawm uniformity ntawm reactant gas sib tov

II. Tej yam tsis xws luag ntawmtantalum carbide txheej

1. Txheej tawg thiab tev

Linear thermal expansion coefficient linear CTE:

2. Kev soj ntsuam tsis zoo:

(1) Ua rau:

(2) Kev ua tus cwj pwm

① Siv X-ray diffraction thev naus laus zis los ntsuas qhov seem seem.

② Siv Hu Ke txoj cai los kwv yees cov kev ntxhov siab uas seem.

(3) Cov qauv tsim muaj

3.Txhim kho cov neeg kho tshuab compatibility ntawm txheej thiab substrate

(1) Nto hauv-situ loj hlob txheej

Thermal reaction deposition and diffusion technology TRD

Molten ntsev txheej txheem

Simplify cov txheej txheem ntau lawm

Txo cov tshuaj tiv thaiv kub

Tus nqi qis dua

Ntau tus phooj ywg environmentally

Haum rau loj-scale industrial ntau lawm

(2) Composite hloov txheej

Kev sib koom ua ke

CVDtxheej txheem

Multi-component txheej

Kev sib xyaw kom zoo ntawm txhua qhov sib xyaw

Flexibly kho cov txheej txheej thiab kev faib ua feem

4. Cov tshuaj tiv thaiv thermal deposition thiab diffusion tshuab TRD

(1) Reaction Mechanism

TRD thev naus laus zis tseem hu ua txheej txheem embedding, uas siv boric acid-tantalum pentoxide-sodium fluoride-boron oxide-boron carbide system los npaj.tantalum carbide txheej.

① Molten boric acid dissolves tantalum pentoxide;

② Tantalum pentoxide raug txo kom muaj zog tantalum atoms thiab diffuses ntawm graphite nto;

③ Active tantalum atoms yog adsorbed ntawm graphite nto thiab hnov ​​​​mob nrog carbon atoms rau daim ntawv.tantalum carbide txheej.

(2) Cov Lus Qhia Tseem Ceeb

Hom carbide txheej yuav tsum ua raws li qhov yuav tsum tau ua kom oxidation tsim dawb lub zog ntawm cov khoom tsim cov carbide siab dua li ntawm boron oxide.

Gibbs dawb lub zog ntawm cov carbide tsawg txaus (tsis li ntawd, boron lossis boride tuaj yeem tsim).

Tantalum pentoxide yog nruab nrab oxide. Nyob rau hauv high-temperature molten borax, nws muaj peev xwm hnov ​​​​mob nrog lub zog alkaline oxide sodium oxide los ua sodium tantalate, yog li txo qhov kub thiab txias.