Hoʻoheheʻe hopena
ʻO ka hopena sinteringkeramika silicon carbideʻO ke kaʻina hana e komo pū ana me ka hoʻopili ʻana o ka seramika, ka hoʻopili ʻana o ka mea hoʻopili ʻana o ka flux infiltration, ka hoʻomākaukau ʻana i ka huahana seramika sintering, ka hoʻomākaukau ʻana i ka seramika lāʻau silicon carbide a me nā ʻanuʻu ʻē aʻe.
ʻO ka nozzle silicon carbide sintering pane
ʻO ka mea mua, 80-90% o ka pauka seramika (i haku ʻia me hoʻokahi a ʻelua paha pauka opauka silicon carbidea me ka pauka boron carbide), 3-15% o ka pauka kumu kalapona (i haku ʻia me hoʻokahi a ʻelua paha o ka ʻeleʻele kalapona a me ka resin phenolic) a me 5-15% o ka mea hoʻoheheʻe (phenolic resin, polyethylene glycol, hydroxymethyl cellulose a paraffin paha) i hui like ʻia me ka hoʻohana ʻana i kahi wili pōpō e loaʻa ai kahi pauka i hui ʻia, kahi i pīpī ʻia a hoʻomaloʻo ʻia, a laila kaomi ʻia i loko o kahi ʻōmole e loaʻa ai kahi compact ceramic me nā ʻano kikoʻī like ʻole.
ʻO ka lua, ua hui like ʻia ka 60-80% pauka silicon, 3-10% pauka silicon carbide a me 37-10% pauka boron nitride, a kaomi ʻia i loko o kahi ʻōmole e loaʻa ai kahi mea hoʻopili sintering flux infiltration agent.
A laila hoʻopili ʻia ka compact ceramic a me ka sintered infiltrant compact, a hoʻokiʻekiʻe ʻia ka mahana i 1450-1750 ℃ i loko o ka umu hakahaka me ke kekelē hakahaka ʻaʻole i emi iho ma mua o 5 × 10-1 Pa no ka sintering a me ka mālama ʻana i ka wela no 1-3 mau hola e loaʻa ai kahi huahana seramika sintered reaction. Hoʻopau ʻia ke koena infiltrant ma luna o ka ʻili o ka seramika sintered ma ke kī ʻana e loaʻa ai kahi pepa seramika mānoanoa, a mālama ʻia ke ʻano mua o ka compact.
ʻO ka mea hope loa, ua hoʻohana ʻia ke kaʻina hana sintering reaction, ʻo ia hoʻi, ʻo ka silicon wai a i ʻole ka hui silicon me ka hana hopena ma ke ana wela kiʻekiʻe e komo i loko o ka blank seramika porous i loaʻa ke kalapona ma lalo o ka hana o ka ikaika capillary, a pane pū me ke kalapona ma laila e hana i ka silicon carbide, kahi e hoʻonui ʻia i ka nui, a ua hoʻopiha ʻia nā pores i koe me ka silicon elemental. Hiki i ka blank seramika porous ke kalapona maʻemaʻe a i ʻole ka silicon carbide/carbon-based composite material. Loaʻa ka mea mua ma ka hoʻōla catalytically a me ka pyrolyzing i kahi resin organik, kahi mea hana pore a me kahi solvent. Loaʻa ka mea hope ma ka pyrolyzing ʻana i nā ʻāpana silicon carbide/resin-based composite materials e loaʻa ai ka silicon carbide/carbon-based composite materials, a i ʻole ma ka hoʻohana ʻana i ka α-SiC a me ka pauka kalapona ma ke ʻano he mau mea hoʻomaka a me ka hoʻohana ʻana i ke kaʻina hana kaomi a i ʻole injection molding e loaʻa ai ka mea composite.
Sintering kaomi ʻole
Hiki ke hoʻokaʻawale ʻia ke kaʻina hana sintering pressureless o ka silicon carbide i ka sintering solid-phase a me ka sintering liquid-phase. I nā makahiki i hala iho nei, ua hoʻomohala ʻia ka noiʻi ma luna onā keramika silicon carbidema ka home a me waho ua kālele nui ʻia i ka sintering pae wai. ʻO ke kaʻina hana hoʻomākaukau keramika: wili pōpō mea hui–> granulation spray–> kaomi maloʻo–> solidification kino ʻōmaʻomaʻo–> sintering vacuum.
Nā huahana silicon carbide sintered pressureless
E hoʻohui i 96-99 mau ʻāpana o ka pauka silicon carbide ultrafine (50-500nm), 1-2 mau ʻāpana o ka pauka boron carbide ultrafine (50-500nm), 0.2-1 mau ʻāpana o ka nano-titanium boride (30-80nm), 10-20 mau ʻāpana o ka resin phenolic hoʻoheheʻe wai, a me 0.1-0.5 mau ʻāpana o ka mea hoʻolaha kiʻekiʻe i ka wili pōpō no ka wili pōpō a me ka hui ʻana no 24 mau hola, a hoʻokomo i ka slurry i hui ʻia i loko o kahi pahu hui no ka hoʻoulu ʻana no 2 mau hola e wehe i nā pehu i loko o ka slurry.
Hoʻopīpī ʻia ka hui ʻana i luna i loko o ka hale kiaʻi granulation, a loaʻa ka pauka granulation me ke ʻano maikaʻi o nā ʻāpana, ka wai maikaʻi, ka laulā hoʻolaha ʻāpana haiki a me ka makū kūpono ma o ka kaohi ʻana i ke kaomi pīpī, ka mahana komo ea, ka mahana puka ea a me ka nui o nā ʻāpana pepa pīpī. ʻO ka hoʻololi alapine centrifugal he 26-32, ʻo ka mahana komo ea he 250-280 ℃, ʻo ka mahana puka ea he 100-120 ℃, a ʻo ke kaomi komo slurry he 40-60.
Hoʻokomo ʻia ka pauka granulation i luna i loko o kahi ʻōmole carbide cemented no ke kaomi ʻana e loaʻa ai kahi kino ʻōmaʻomaʻo. ʻO ke ʻano kaomi ʻana he kaomi bidirectional, a ʻo ke kaumaha o ka mīkini hana he 150-200 tons.
Hoʻokomo ʻia ke kino ʻōmaʻomaʻo i kaomi ʻia i loko o ka umu hoʻomaloʻo no ka hoʻomaloʻo ʻana a me ka hoʻōla ʻana e loaʻa ai ke kino ʻōmaʻomaʻo me ka ikaika kino ʻōmaʻomaʻo maikaʻi.
Ua kau ʻia ke kino ʻōmaʻomaʻo i hoʻōla ʻia ma luna i loko o kahiipu hoʻoheheʻe graphitea hoʻonohonoho pono ʻia a maikaʻi hoʻi, a laila waiho ʻia ka ipu hoʻoheheʻe graphite me ke kino ʻōmaʻomaʻo i loko o ka umu sintering vacuum wela kiʻekiʻe no ke ahi ʻana. ʻO ka mahana ahi he 2200-2250 ℃, a ʻo ka manawa insulation he 1-2 mau hola. ʻO ka hope loa, loaʻa nā keramika silicon carbide sintered pressureless kiʻekiʻe.
Sintering pae paʻa
Hiki ke hoʻokaʻawale ʻia ke kaʻina hana sintering ʻole o ka silicon carbide i ka sintering pae paʻa a me ka sintering pae wai. Pono ka sintering pae wai i ka hoʻohui ʻana o nā mea hoʻohui sintering, e like me nā mea hoʻohui binary a me ternary Y2O3, e hana iā SiC a me kāna mau mea hui pū ʻia e hōʻike i ka sintering pae wai a hoʻokō i ka densification ma kahi mahana haʻahaʻa. ʻO ke ʻano hoʻomākaukau o nā keramika silicon carbide sintered pae paʻa e pili ana i ka hui ʻana o nā mea maka, ka granulation spray, ka hoʻoheheʻe ʻana, a me ka sintering vacuum. Penei ke kaʻina hana kikoʻī:
Hoʻokomo ʻia he 70-90% o ka submicron α silicon carbide (200-500nm), 0.1-5% o ka boron carbide, 4-20% o ka resin, a me 5-20% o ka mea hoʻopaʻa organik i loko o kahi mea hui a hoʻohui ʻia me ka wai maʻemaʻe no ka hui ʻana i ka pulu. Ma hope o 6-48 mau hola, ua hoʻohele ʻia ka slurry i hui ʻia ma o kahi sieve 60-120 mesh;
ʻO ka slurry i kānana ʻia e pīpī ʻia ma o kahi hale kiaʻi granulation pīpī. ʻO ka mahana komo o ka hale kiaʻi granulation pīpī he 180-260 ℃, a ʻo ka mahana puka he 60-120 ℃; ʻo ka nui o ka mea granulated he 0.85-0.92g/cm3, ʻo ke kahe ʻana he 8-11s/30g; ua kānana ʻia ka mea granulated ma o kahi sieve 60-120 mesh no ka hoʻohana ma hope.
E koho i kahi ʻōpala e like me ke ʻano o ka huahana i makemake ʻia, e hoʻouka i ka mea granulated i loko o ka lua ʻōpala, a hana i ka hoʻoheheʻe ʻana i ka mahana o ka lumi ma ke kaomi o 50-200MPa e loaʻa ai ke kino ʻōmaʻomaʻo; a i ʻole e kau i ke kino ʻōmaʻomaʻo ma hope o ka hoʻoheheʻe ʻana i ka compression i loko o kahi mea kaomi isostatic, e hana i ke kaomi isostatic ma ke kaomi o 200-300MPa, a loaʻa ke kino ʻōmaʻomaʻo ma hope o ke kaomi lua;
E hoʻokomo i ke kino ʻōmaʻomaʻo i hoʻomākaukau ʻia ma nā ʻanuʻu i luna i loko o ka umu sintering vacuum no ka sintering, a ʻo ka mea kūpono ʻo ia ka seramika bulletproof silicon carbide i hoʻopau ʻia; i ke kaʻina hana sintering i luna, e hoʻokuʻu mua i ka umu sintering, a i ka wā e hiki ai ke kekelē vacuum i 3-5 × 10-2 Ma hope o Pa, e hoʻokomo ʻia ke kinoea inert i loko o ka umu sintering i ke kaomi maʻamau a laila hoʻomehana ʻia. ʻO ka pilina ma waena o ka mahana hoʻomehana a me ka manawa: ka mahana o ka lumi a i 800 ℃, 5-8 mau hola, mālama wela no 0.5-1 hola, mai 800 ℃ a i 2000-2300 ℃, 6-9 mau hola, mālama wela no 1 a 2 mau hola, a laila hoʻomaʻalili ʻia me ka umu a hoʻokuʻu ʻia i ka mahana o ka lumi.
ʻO ke ʻano liʻiliʻi a me ka palena palaoa o ka silicon carbide sintered ma ke kaomi maʻamau
I ka pōkole, ʻoi aku ka maikaʻi o ka hana o nā keramika i hana ʻia e ke kaʻina hana sintering wela, akā ua hoʻonui nui ʻia ke kumukūʻai hana; ʻoi aku ka nui o nā koi mea maka o nā keramika i hoʻomākaukau ʻia e ka sintering pressureless, kiʻekiʻe ka mahana sintering, nui nā loli nui o ka nui o ka huahana, kaʻina hana paʻakikī a me ka hana haʻahaʻa; ʻoi aku ka nui o ka density o nā huahana keramika i hana ʻia e ke kaʻina hana sintering reaction, maikaʻi ka hana anti-ballistic, a haʻahaʻa ke kumukūʻai hoʻomākaukau. Loaʻa i nā ʻano hana hoʻomākaukau sintering like ʻole o nā keramika silicon carbide ko lākou mau pono a me nā hemahema, a ʻokoʻa hoʻi nā hiʻohiʻona noi. ʻO ke kulekele maikaʻi loa ke koho ʻana i ke ʻano hoʻomākaukau kūpono e like me ka huahana a loaʻa ke kaulike ma waena o ke kumukūʻai haʻahaʻa a me ka hana kiʻekiʻe.
Ka manawa hoʻouna: ʻOkakopa-29-2024