Alumina ceramics a wɔyɛ no ho nhyehyɛe .
Powder ahosiesie .
Wɔsiesie aluminum oxide powder a ɛwɔ adwumayɛbea hɔ no yɛ no powder nneɛma sɛnea ɛsono nea wɔyɛ ne nwene akwan horow. Nneɛma nketenkete a ɛwɔ powder no mu no nnu 1μm, sɛ wɔyɛ alumina a ɛwɔ alumina a ɛho tew wɔ 99.99% mu a, ɛyɛ alumina ceramic products a ɛkorɔn no, nanso ehia sɛ wɔyɛ ultrafine grinding na wɔyɛ ne particle size distribution uniform no nso. Sɛ wɔde extrusion molding anaa injection molding di dwuma a, ɛsɛ sɛ wɔde binders ne plasticizers hyɛ powder no mu, mpɛn pii no thermoplastics anaasɛ resins a emu duru yɛ 10-30%. Ɛsɛ sɛ wɔde organic binder no fra alumina powder no pɛpɛɛpɛ wɔ 150-200 temperature mu na ama nsusuwso adwuma no ayɛ mmerɛw. Ɛho nhia sɛ powder ade a ɛnam ɔhyew a wɔde mia so yɛ no so no de binder ka ho. Sɛ wɔde semi-automatic anaasɛ automatic dry pressing molding di dwuma a, powder no wɔ process ahwehwɛde soronko, na ɛho hia sɛ wɔde spray granulation kwan di dwuma de sa powder no na wɔma ɛyɛ te sɛ nea ɛyɛ kurukuruwa, sɛnea ɛbɛyɛ a powder no bɛkɔ nsu mu yiye na ama ayɛ mmerɛw sɛ wɔbɛma nsusuwso no ɔfasu no ayɛ nea ɛyɛ adwuma ankasa wɔ nsusuwso no mu. Nea ɛka ho no, sɛnea ɛbɛyɛ a ɛbɛtew powder no ne nkuku no fasu no ntam no so no, ɛho hia sɛ wɔde srade no 1 kosi 2% ka ho, te sɛ stearic acid, ne binder PVA.
Sɛnea ɛbɛyɛ na press molding no ayow no, ɛho hia sɛ wɔde powder spray granulation ba, a wɔde polyvinyl alcohol ba sɛ ade a wɔde kyekyere nneɛma ho. Nhwehwɛmu asoɛe bi a ɛwɔ Shanghai yɛɛ nsuo-soluble paraffin wax sɛ binder ma AL203 spray granulation, a ɛwɔ nsuo pa wɔ ɔhyew ase. Ɛsɛ sɛ powder a wɔde petepete granulation akyi no nya nsu pa, loose density, ne flow angle friction temperature a ennu digrii 30 . Sɛnea ɛbɛyɛ a wobenya blank density a ɛkorɔn no, ratio of particle size yɛ nea eye sen biara.
Ɔkwan a wɔfa so yɛ .
Akwan a wɔfa so yɛ alumina ceramic nneɛma no bi ne dry pressing, grouting, extrusion, awɔw isostatic pressing, injection, casting, hot pressing ne hot isostatic pressing. Wɔ nnansa yi mfe mu no, wɔ fie ne amannɔne ayɛ filter molding, direct solidification injection molding, gel injection molding, centrifugal injection molding ne solid free molding mfiridwuma. Nneɛma ahorow a wɔde yɛ nneɛma, ne kɛse, ne nsusuwii a ɛyɛ den ne nneɛma a wɔyɛ no pɛpɛɛpɛ no hwehwɛ akwan horow a wɔfa so yɛ nneɛma.
Nnianim asɛm a ɛfa ne common forming ho:
1, dry press molding: Alumina ceramic dry press molding mfiridwuma no yɛ nea ɛyɛ mmerɛw ne ne mu ɔfasu no mu duru a ɛboro 1mm, ne tenten ne ne kɛse nsusuwii nyɛ kɛse nsen 4:1 nneɛma. Akwan a wɔfa so yɛ nneɛma no yɛ nea ɛne ne ho hyia anaasɛ ɛyɛ akwan abien. Press no wɔ hydraulic type ahorow abien ne mfiridwuma mu su, a ebetumi ayɛ semi-a ɛyɛ adwuma anaasɛ ɛyɛ adwuma ankasa. Nhyɛso a ɛsen biara a wɔde mia no yɛ 200MPa. Output no betumi adu 15 ~ 50 asinasin wɔ simma biara mu. Esiane sɛ hydraulic press no nhyɛso a ɛyɛ pɛ no yɛ pɛ nti, ɛsono sɛnea afã horow a wɔde mia no no sorokɔ yɛ soronko bere a ɛsono powder a wɔde hyɛ mu ma no. Nhyɛso a mfiri a wɔde tintim no de ba no kɛse gu ahorow esiane powder a wɔde hyɛ mu ma no dodow nti, na ɛnyɛ den sɛ ɛbɛma nsonsonoe a ɛwɔ kɛse no mu no ayɛ kɛse bere a wɔayɛ no sintering akyi na ɛka sɛnea ade no te no. Enti, powder particles a ɛwɔ dry pressing process no mu a wɔkyekyɛ no pɛpɛɛpɛ no ho hia yiye ma nsusuwso a wɔde hyɛ mu ma. Sɛ́ ebia dodow a wɔde hyɛ mu no yɛ pɛpɛɛpɛ anaasɛ ɛnte saa no nya nkɛntɛnso kɛse wɔ alumina ceramic afã horow a wɔayɛ no dimensional pɛpɛɛpɛ so. Powder particles a ɛboro 60μm, ntam 60 ~ 200 mesh betumi anya maximum free flow effect, na ama wɔanya nhyɛso molding effect a eye sen biara.
2, Grouting Molding Method: Grouting Molding ne ɔkwan a wɔfa so yɛ nneɛma a edi kan koraa a wɔde yɛ alumina nkuku. Esiane sɛ wɔde gypsum nsusuwso di dwuma nti, ɛho ka no sua na ɛnyɛ den sɛ wɔbɛyɛ afã horow a ɛyɛ kɛse na ɛyɛ den. Ade titiriw a ɛwɔ grouting molding mu ne alumina slurry a wosiesie. Mpɛn pii no wɔde nsu di dwuma sɛ nsu a wɔde fa nsu mu, na afei wɔde degumming aduru ne binder no ka ho, bere a wɔayɛ no yiye awie no, wɔde gas no gu, na afei wɔde plaster nsunsu no gu akyi. Esiane sɛ nsu a ɛwɔ plaster nkuku no ntini mu no twetwe nsu nti, nsu a ɛyɛ fĩ no yɛ den wɔ nkuku no mu. Wɔ grouting a ɛyɛ tokuru mu no, ɛsɛ sɛ wohwie nsu a ɛboro so no gu bere a slurry a ɛtwetwe wɔ nkuku no fasu no so no du nea ɛho hia no mu. Sɛnea ɛbɛyɛ a nipadua no so bɛtew no, ɛsɛ sɛ wɔde nsu a ɛdɔɔso di dwuma sɛnea ɛbɛyɛ yiye biara.
Ɛsɛ sɛ wɔde nneɛma a wɔde ka ho nso ka alumina ceramic slurry no ho ma ɛyɛ anyinam ahoɔden a ɛbɔ ho abien wɔ slurry particles no ani sɛnea ɛbɛyɛ a slurry no bɛsensɛn hɔ a ɛrensiesie. Bio nso, wɔde binders te sɛ vinyl alcohol, methyl cellulose, alginate amine ne dispersants te sɛ polyacrylamide ne gum Arabic ka ho na ama slurry no ayɛ nea ɛfata ma grouting molding operation.
