Alpha Si3N4 Silicon Nitride

 

Silicon nitride yog ib qho inorganic tshuaj nrog cov tshuaj formula Si3N4. Nws yog ib qho tseem ceeb structural ceramic khoom nrog siab hardness, inherent lubrication, hnav tsis kam thiab atomic crystals; tiv taus oxidation ntawm qhov kub thiab txias. Tsis tas li ntawd, nws tuaj yeem tiv taus qhov txias thiab kub. Nws yuav tsis tawg yog tias nws tau kub ntau tshaj 1000 degrees Celsius hauv huab cua, txias sai sai, thiab tom qab ntawd cua sov sai sai.

 

 

 

	-Si3N4
Crystal Structure	hexagonal Si3N4 theem;
Qhov ntom	qis ntom piv rau -Si3N4;
Kub stability	ruaj khov ntawm qhov kub thiab txias, feem ntau txog li 1300 degree;
Cov khoom	zoo oxidation kuj ntawm nruab nrab kub, thiab yog haum rau daim ntaub ntawv uas high-temperature stability tsis tas yuav tsum tau;

 

Silicon nitride txheej txheem ntau lawm

Raws li cov txheej txheem tsim khoom, cov khoom siv silicon nitride tuaj yeem muab faib ua cov tshuaj tiv thaiv sintering, cov khoom siv kub kub, cov khoom siv hauv tsev sintering, cov khoom siv siab isostatic thiab cov khoom siv rov ua dua tshiab. Ntawm lawv, cov tshuaj tiv thaiv sintering yog ib txoj hauv kev los ua silicon nitride refractory khoom.

 

Cov tshuaj tiv thaiv sintering txoj kev tsim cov khoom siv silicon nitride yog cov hmoov av silicon hmoov (nrog rau qhov loj me feem ntau tsawg dua 80 μm) yog tsim los ntawm tshuab lossis isostatic nias. Tom qab lub cev ntsuab qhuav, nws yog rhuab hauv nitrogen rau 1350 - 1400 degree . Thaum lub sij hawm sintering, nitriding tshwm sim ib txhij. Nrog rau txoj kev tsim khoom no, cov xwm txheej ntawm cov khoom siv raw, cov txheej txheem tua hluav taws thiab cov huab cua zoo heev cuam tshuam rau kev ua haujlwm ntawm cov khoom.

 

Silicon hmoov muaj ntau yam impurities xws li Fe, Ca, Al, Ti, thiab lwm yam. Fe yog suav tias yog ib qho catalyst hauv cov txheej txheem tshuaj tiv thaiv. Nws tuaj yeem txhawb nqa qhov sib txawv ntawm silicon, tab sis tib lub sijhawm nws tuaj yeem ua rau muaj qhov tsis xws luag xws li pores. Lub luag haujlwm tseem ceeb ntawm Fe ua ib qho ntxiv: nws tuaj yeem siv los ua cov khoom siv hauv cov txheej txheem tshuaj tiv thaiv los txhawb kev tsim ntawm SiO2 oxide zaj duab xis rau ntawm qhov chaw ntawm cov khoom; Txhawm rau tsim cov hlau silicate molten system, nitrogen yaj hauv cov kua FeSi2 thiab txhawb kev tsim ntawm -Si3N4. Txawm li cas los xij, yog tias cov khoom hlau loj dhau los yog cov ntsiab lus siab dhau lawm, nws tseem yuav ua rau muaj qhov tsis xws luag xws li pores hauv cov khoom, uas yuav txo nws txoj kev ua haujlwm. Feem ntau, 0 rau 5% ntawm hlau yog ntxiv. Cov impurities xws li Al, Ca thiab Ti tuaj yeem yooj yim tsim eutectic nrog silicon. Kev sib ntxiv txaus tuaj yeem txhawb nqa sintering thiab txhim kho kev ua haujlwm ntawm cov khoom.

 

Qhov zoo dua qhov me me ntawm cov hmoov silicon thiab qhov loj dua ntawm qhov chaw tshwj xeeb, qhov kub ntawm sintering tuaj yeem ua tau. Piv nrog cov hmoov av silicon ntawm qhov loj me me, cov ntsiab lus ntawm -Si3N4 hauv cov khoom yog siab dua rau cov hmoov zoo silicon. Txo qhov me me ntawm cov hmoov silicon tuaj yeem txo qhov microscopic pore loj ntawm cov khoom. Qhov tseeb particle loj piv yuav ua rau kom qhov ntom ntawm cov khoom.

Qhov kub thiab txias muaj qhov cuam tshuam zoo rau kev ceev nitriding. Cov tshuaj tiv thaiv nitriding pib ntawm 970-1000 degree , thiab cov tshuaj tiv thaiv ceev nce mus txog 1250 degree . Nyob rau hauv lub siab kub theem, yog hais tias qhov kub ceev tshaj qhov melting point ntawm silicon (1420 degree), silicon txaus yuav yooj yim tshwm sim vim exothermic cov tshuaj tiv thaiv, ua rau cov hmoov silicon yaj thiab yaj.

 

 

 

 

 

 

 

 

 

 

Q: Koj them tus nqi coj mus kuaj li cas?
A: Yog tias koj xav tau cov qauv ntawm peb cov Tshuag, peb tuaj yeem muab rau koj dawb, tab sis tus nqi dawb yuav tsum nyob ntawm koj sab. Yog tias koj xav tau qhov tshwj xeeb loj, Peb yuav tsub tus nqi ua piv txwv uas yuav tau them rov qab thaum koj tso qhov kev txiav txim.
Q: Koj lub sijhawm khoom xa tuaj yog dab tsi?
A: Yog tias peb muaj Tshuag, tuaj yeem xa hauv 1-7 hnub; yog tias tsis muaj Tshuag, xav tau 5-30 hnub, nyob ntawm seb muaj pes tsawg.

 

Q: Koj qhov zoo yog dab tsi?

A: Peb muaj peb tus kheej lub Hoobkas, cov neeg ua haujlwm zoo nkauj thiab cov kws tshaj lij kev tsim khoom thiab kev ua haujlwm thiab pab pawg muag khoom. Zoo tuaj yeem lav. Peb muaj kev nplua nuj nyob hauv metallurgical steelmaking teb.

Q: Puas yog tus nqi sib tham?

A: Yog, thov hu rau peb txhua lub sijhawm yog tias koj muaj lus nug. Thiab rau cov neeg siv khoom uas xav kom ua lag luam loj, peb yuav ua qhov zoo tshaj plaws los txhawb.

 

Cim npe nrov: Tuam Tshoj alpha si3n4 silicon nitride manufacturers, lwm tus neeg, Hoobkas