(1) Dɔte-a wɔde abɔ silicon carbide birikisi
Dɔte-bonded silicon carbide birikisi yɛ nneɛma a ogya ntumi nhyew a wɔde silicon carbide titiriw na ɛyɛ dɔte a ɛyɛ bonding agent. Wɔn su ne ɔhyew a ɛkɔ soro, ɔhyew ntrɛwmu nsusuwii a ɛba fam, ne ɔhyew a ɛbɔ ne nea ɛko tia a ɛkyɛn so, na wogyina hɔ ma birikisi a edi kan a egyina silicon carbide- so a wɔyɛe.
Saa birikisi yi de silicon carbide tuntum di dwuma sɛ ade a wɔde yɛ, a nnuru a ɛwɔ mu ne: SiC 98.0%, free C 0.5%, Fe 0.2%, ne free SiO2 0.6%. Dɔte a ɛyɛ mmerɛw a ɛwɔ bonding su pa ne pulp waste liquor yɛ nneɛma a ɛkyekyere. Bere a abakɔsɛm mu no, wɔde dɔte a ɛka bom (a ɛtaa yɛ 10%–15%) dii dwuma no, mprempren adeyɛ no pɛ sɛ wɔde dɔte 3% ne nsa a wɔsɛe no 5% a wɔde ayɛ pulp ka bom. Biriki a dɔte a ɛwɔ mu no sua no da ɔhyew a ɛkɔ soro mprɛnsa kosi anan adi sen nea dɔte pii wom, ne adesoa a ɛkorɔn-a ɛsoa ɔhyew a ɛyɛ mmerɛw ne slag a ɛko tia. Ɔkwan a wɔfa so yɛ birikisi a dɔte 3% wom no hwehwɛ sɛ wɔde SiC nneɛma nketenkete a ɛyɛ mmerɛw, ɛyɛ mfinimfini, ne nea ɛyɛ fɛ frafra na ama wɔanya dodow a ɛsen biara. Sɛ wɔde dɔte no fra mu yiye wie a, wɔde ka ho; akyi simma 3 foforo a wɔde frafra dry no, wɔde 4% pulp waste liquor (density 1.26–1.28 g/cm3) ba ma wɔde fra nsuo mu. Nsuo a ɛwɔ afrafradeɛ no mu no bɛyɛ 1.5%. Sɛ wɔde nnɔnhwerew 12-anyin akyi a, wɔde afrafrade no fa 4 mm sieve mu na wɔde birikisi press na ɛyɛ. Biriki a ɛyɛ ahabammono no dodow fi 2.5 kosi 2.7 g/cm3. Wɔde mframa ma birikisi no we nnafua 2–4 na afei wɔde gya gu fononoo a wɔde fa mu a ɛyɛ digrii 1400 mu .
Wɔde saa nneɛma yi yɛ dɔte fononoo mu nneɛma (te sɛ batts, supports, ne saggers), muffle fononoo kataso, linings ma aluminium refining fononoo, distillation retorts ma zinc distillation fononoo, ne coolers ma cement rotary fononoo.
(2) Silicon nitride-a wɔde abɔ silicon carbide birikisi
Silicon nitride-bonded silicon carbide bricks yɛ nneɛma a ɛtumi nhyew a wɔde SiC ne Si powders na ɛyɛ denam nitriding ne ogya a wɔde yɛ adwuma so. Wɔn su ne silicon nitride (Si3N4) bonding phase. Si3N4 no wɔ hɔ sɛ acicular (needle-te sɛ) anaa fibrous crystals a ɛda silicon carbide (SiC) aburow no ntam, na ɛma eyi yɛ ade a ɛho hia a ɛkɔ anim a ɛtumi nhyew.
Bere a wɔde nnyinasosɛm a ɛne sɛ wɔbɛyɛ ade a wɔde yɛ ade no di dwuma no, wɔde SiC nipadua a ɛyɛ ahabammono a silicon powder wom no yɛ sinter denam nitridation adeyɛ so; ogya a wɔtow no kɔ so wɔ fononoo a wɔatoto mu a nitrogen wim tebea wom mu, na ɛma wotumi di so pɛpɛɛpɛ. Wɔahyɛ fononoo mu hyew, nhyɛso, ne wim tebea ho nhyehyɛe denneennen. Nneɛma atitiriw a wɔde yɛ adwuma no bi ne: nitriding gas nhyɛso a ɛyɛ 0.02–0.04 MPa, fononoo wim oxygen dodow a ɛba fam sen 0.01%, ne nitridation hyew a etwa to a ɛyɛ 1350–1450℃; nitridation bere nyinaa gu ahorow gyina sɛnea ade no te ne ne kɛse so.
Silicon nitride-bonded silicon carbide birikisi da ahoɔden a ɛkyɛn so adi wɔ alkali erosion ho, ɛko tia nsuo a ɛnam cryolite a wɔayam so, ɛko tia oxidation, ɛko tia, ɛko tia ɔhyew a ɛkɔ soro, ɛko tia thermal shock, ne anyinam ahoɔden a ɛba fam koraa.
Wɔde saa birikisi yi di dwuma titiriw sɛ nneɛma a wɔde kata fononoo a ano yɛ den a ɛwɔ fam no so, na ɛma wonya nkwa nna a ɛboro nea wɔde di dwuma wɔ tete mmere mu de mmɔho abien. Bio nso, wɔyɛ sɛ linings ma aluminium reduction cells ne sɛ ceramic furniture-a ɛde mfasoɔ te sɛ ahoɔden a wɔkora so, dwumadie nkwa nna a ɛtrɛ, ne nneɛma a atwa yɛn ho ahyia adamfofa-na wɔde di dwuma nso sɛ sleeve bricks ma nsuo-cooled blast furnace tuyeres.
(3) Silicon Carbide Nneɛma a Wɔasan ayɛ no Ahwehwɛ
Silicon carbide a wɔasan ayɛ no ahwehwɛ yɛ nneɛma a ɛmma ogya ntumi nhyew a wɔde silicon carbide nneɛma a wɔde yɛ nneɛma a wɔde yɛ nneɛma, a nea ɛda nsow ne sɛ silicon carbide aburow no bom tẽẽ. Wɔda nsow denam ɔfã a ɛto so abien a enni hɔ, a ne nyinaa yɛ 100% -SiC. Nnuru a ɛwɔ nneɛma a wɔde yɛ silicon carbide a wɔasan ayɛ no mu no te sɛ nea edidi so yi: SiC 99.5%, free C 0.2%, Fe 0.08%, ne free SiO2 0.08%.
Wɔde silicon carbide nneɛma a wɔasan ayɛ no ahwehwɛ titiriw di dwuma sɛ fononoo mu nneɛma, na ɛde mfaso horow te sɛ ahoɔden a wɔkora so, fononoo dodow a etu mpɔn a ɛkɔ soro, ogya a wɔtow no tiaa, nneɛma a wɔyɛ no yiye a ɛkɔ anim, ne sikasɛm mu mfaso kɛse ma. Wɔde yɛ ɔhyew afiri a wɔde hyew nneɛma, nsukorade a wɔde dɔte ayɛ a ɛhyerɛn, ne nsukorade a ɛbɔ nneɛma a ɛwom ho ban (titiriw wɔ fononoo a ɛwɔ wim mu) nso.