ʻO kēlā me kēia mea i hana ma nā ʻoihana abrasives, refractories, a i ʻole keramika, ʻike lākou i kēlācarbide silicon ʻōmaʻomaʻoHe mea paʻakikī loa ka hana ʻana me ka micropowder. ʻO kēia mea, me ka paʻakikī e kokoke ana i ka daimana a me ka conductivity thermal a me ka uila maikaʻi loa, kūpono maoli no ka wili pololei, nā refractories kiʻekiʻe, a me nā keramika kūikawā. Eia nō naʻe, ʻaʻole lawa ka noʻonoʻo wale ʻana i kona paʻakikī e hoʻohana pono ai - he nui aku nā mea i loko o kēia pauka ʻōmaʻomaʻo maʻamau ma mua o ka mea i ʻike ʻia. Aia ke kī i ka "nui o ka ʻāpana."
ʻŌlelo pinepine nā ʻenekinia mea akamai, "I ka loiloi ʻana i kahi mea, e nānā mua i ka pauka; i ka loiloi ʻana i ka pauka, e nānā mua i nā ʻāpana." He ʻoiaʻiʻo loa kēia. ʻO ka nui o ka ʻāpana o ka micropowder silicon carbide ʻōmaʻomaʻo e hoʻoholo pololei inā he waiwai ikaika a he mea keakea koʻikoʻi paha ia i nā noi ma hope. I kēia lā, e ʻeli mākou i ke ʻano o ka hoʻomalu ʻia ʻana o kēia nui o ka ʻāpana a me nā pilikia loea e pili ana i ka hoʻokō ʻana i kēia kaohi.
I. "Wili ʻana" a me "Hoʻokaʻawale": He "Kaʻina Hana ʻoki" Pae Micron
No ka loaʻa ʻana o ka idealpauka micropoda silicon carbide ʻōmaʻomaʻo, ʻo ka hana mua, ʻo ia ka "wāwahi" i nā kristal silicon carbide ʻōmaʻomaʻo nui. ʻAʻole kēia he mea maʻalahi e like me ka wāwahi ʻana iā lākou me ka hāmare, akā he hana akahai e pono ai ka pololei loa.
ʻO ke ʻano hana nui, ʻo ia ka wili ʻana i ka mīkini. ʻOiai ke kani ʻino nei, pili ia i ka hoʻomalu pono ʻana. ʻO nā wili pōpō ka "kahua hoʻomaʻamaʻa" maʻamau, akā ʻo ka hoʻohana ʻana i nā pōpō kila maʻamau hiki ke hoʻokomo maʻalahi i nā haumia hao. Hoʻohana nā ʻano hana holomua i kēia manawa i nā uhi keramika a me nā pōpō wili silicon carbide a i ʻole zirconia e hōʻoia i ka maʻemaʻe. ʻAʻole lawa ka wili pōpō wale nō; no ka loaʻa ʻana o ka micropowder maikaʻi a ʻoi aku ka like, ʻoi aku hoʻi ma ka pae sub-10 micrometer (µm), hoʻohana ʻia ka "wili air jet". Hoʻohana kēia ʻenehana i ka ea wikiwiki e hoʻoulu ai i nā ʻāpana e kuʻi a haki i ka friction, e hopena ana i ka haumia liʻiliʻi a me ka hoʻolaha nui o nā ʻāpana. Hoʻomaka ka wili pulu i ka wā e pono ai nā pauka ultra-fine (e laʻa, ma lalo o 1 µm). Pale pono ia i ka hoʻopili ʻana o ka pauka, e hopena ana i nā slurries me ka hoʻopuehu maikaʻi.
Eia naʻe, ʻaʻole lawa ka "kuʻi wale ʻana"; aia ka ʻenehana koʻikoʻi maoli i ka "hoʻokaʻawale ʻana." ʻOkoʻa ka nui o nā pauka i hana ʻia e ka kuʻi ʻana, a ʻo kā mākou pahuhopu ke koho wale i ka nui i makemake ʻia. Ua like kēia me ke koho ʻana i nā ʻāpana one me ke anawaena o 0.5 a 0.6 millimeters mai kahi puʻu one. ʻO nā mīkini hoʻokaʻawale ea maloʻo ka mea i hoʻohana nui ʻia i kēia manawa, e hoʻohana ana i ka ikaika centrifugal a me ka aerodynamics e hoʻokaʻawale i nā pauka coarse a me nā pauka maikaʻi me ka pono kiʻekiʻe a me ka hoʻopuka nui. Akā aia kahi pilikia: i ka wā e lawa ai ka maikaʻi o ka pauka (e laʻa, ma lalo o kekahi mau micrometers), e hui pū nā ʻāpana ma muli o nā ikaika van der Waals (agglomeration), e paʻakikī ai i nā mea hoʻokaʻawale ea ke hoʻokaʻawale pololei iā lākou ma muli o ka nui o nā ʻāpana pākahi. I kēia hihia, hiki i ka hoʻokaʻawale pulu (e like me ka hoʻokaʻawale ʻana o ka centrifugal sedimentation) ke lilo i mea pono i kekahi manawa, akā paʻakikī ke kaʻina hana a piʻi ke kumukūʻai.
No laila, ʻike ʻoe, ʻo ke kaʻina hana hoʻomalu nui o nā ʻāpana holoʻokoʻa he hakakā mau a me ka hoʻokūkū ma waena o ka "kuʻi ʻana" a me ka "hoʻokaʻawale ʻana." ʻO ka kuʻi ʻana e makemake ana i nā ʻāpana maikaʻi aʻe, akā ʻo nā ʻāpana liʻiliʻi loa e maʻalahi i ka hoʻohuihui ʻana, e pale ana i ka hoʻokaʻawale ʻana; ʻo ka hoʻokaʻawale ʻana e makemake ana i ka pololei ʻoi aku, akā pilikia pinepine me nā pauka maikaʻi i hoʻohuihui ʻia. Hoʻolilo nā ʻenekinia i ka hapa nui o ko lākou manawa e kaulike ana i kēia mau koi hakakā.
II. "Nā Mea Keakea" a me nā "Hoʻonā": ʻO nā Kakalaioa a me ke Mālamalama ma ke Ala i ka Mana o ka Nui o nā ʻĀpana
ʻO ka kaohi ʻana i ka nui o nā ʻāpana o ka micropowder silicon carbide ʻōmaʻomaʻo me ka hilinaʻi e pili ana i nā mea ʻoi aku ma mua o ka kuʻi ʻana a me ka hoʻokaʻawale ʻana. Ke kū nei kekahi mau "ala" maoli i ke ala, a me ka ʻole o ka hoʻoponopono ʻana iā lākou, ʻaʻole hiki ke kaohi pololei.
ʻO ke keakea mua, ʻo ia ka hopena i hoʻokumu ʻia e ka "paʻakikī."ʻO ka carbide silicon ʻōmaʻomaʻohe paʻakikī loa ia, e koi ana i ka ikehu nui e wāwahi ai, e hopena ana i ka ʻaʻahu nui o nā lako. I ka wā o ka wili ʻana i nā mea wili maikaʻi loa, ʻo ka ʻaʻahu ʻana o nā mea wili a me nā liners e hana i ka nui o nā haumia. Hoʻohui kēia mau mea haumia i loko o ka huahana, e hoʻopilikia ana i kona maʻemaʻe. ʻO kāu hana nui a pau e kāohi ana i ka nui o nā ʻāpana e lilo i mea ʻole inā kiʻekiʻe loa nā pae haumia. I kēia manawa, ke hoʻomohala nui nei ka ʻoihana i nā mea wili pale ʻaʻahu a me nā mea liner, a me ka hoʻomaikaʻi ʻana i nā ʻano lako, e hakakā me kēia "tiga paʻakikī."
ʻO ka lua o ka tiger ʻo ia ke "kānāwai o ka huki" i loko o ke ao o nā pauka maikaʻi - ka hoʻopili ʻana. ʻO ka ʻoi aku ka maikaʻi o nā ʻāpana, ʻoi aku ka nui o ka ʻili kikoʻī, a ʻoi aku ka kiʻekiʻe o ka ikehu o ka ʻili; ma ke ʻano maoli lākou e "hui pū." Hiki i kēia hoʻopili ʻana ke "hui palupalu" (i hoʻopaʻa ʻia e nā mana intermolecular, e like me nā mana van der Waals, he maʻalahi ke wāwahi), a i ʻole ka "hui paʻakikī" ʻoi aku ka weliweli (kahi i ka wā e kuʻi ai a i ʻole ka calcination, e heheʻe hapa nā ʻili o nā ʻāpana a i ʻole e hana i nā hopena kemika, e hoʻopaʻa pono ana iā lākou). Ke hana ʻia nā agglomerates, hoʻohālike lākou e like me "nā ʻāpana nui" i nā mea hana loiloi nui o nā ʻāpana, e alakaʻi hewa nui ana i kou manaʻo; i nā noi hana, e like me ka hoʻopili ʻana i nā wai, ʻo kēia mau agglomerates nā "kuleana" e kahakaha ana i ka ʻili o ka workpiece. He pilikia honua ka hoʻoponopono ʻana i ka agglomeration. Ma waho aʻe o ka hoʻohui ʻana i nā mea hoʻohui a me ka hoʻomaikaʻi ʻana i ke kaʻina hana i ka wā e kuʻi ai, ʻo kahi ala ikaika loa ka hoʻololi ʻana i ka ʻili o ka pauka, e hāʻawi ana iā ia i kahi "uhi" e hōʻemi i ka ikehu o ka ʻili a pale iā ia mai ka makemake mau e "hui pū."
ʻO ke kolu o ka tiga ka maopopo ʻole o ke "ana."
Pehea ʻoe e ʻike ai ʻo ka nui o ka ʻāpana āu i hoʻomalu ai ʻo ia ka mea āu e manaʻo ai? ʻO nā mea kālailai nui o ka ʻāpana ko mākou mau maka, akā ʻo nā loina ana like ʻole (laser diffraction, sedimentation, image analysis), a me nā ʻano hoʻolaha laʻana like ʻole ma lalo o ke kumumanaʻo like, hiki ke hāʻawi i nā hopena like ʻole. He ʻoiaʻiʻo loa kēia no nā pauka i hoʻopili mua ʻia; inā ʻaʻole i hoʻokō ʻia ka hoʻolaha kūpono ma mua o ke ana ʻana (e laʻa, me ka hoʻohui ʻana i nā mea hoʻolaha, ka mālama ʻana i ka ultrasonic), e mamao loa ka ʻikepili i loaʻa mai ke kūlana maoli. Me ka ʻole o ke ana hilinaʻi, he kamaʻilio lapuwale wale nō ka mana pololei.
ʻOiai kēia mau pilikia, ke ʻimi mau nei ka ʻoihana i nā hoʻonā. No ka laʻana, ʻo ka hoʻomaʻemaʻe a me ke akamai o ke kaʻina holoʻokoʻa he ʻano nui ia. Ma o nā lako nānā nui o ka ʻāpana pūnaewele, ʻo ka pane ʻikepili manawa maoli a me ka hoʻoponopono ʻakomi o nā palena kuʻi a me ka hoʻokaʻawale ʻana e alakaʻi i kahi kaʻina hana paʻa. Eia kekahi, ke loaʻa nei ka ʻenehana hoʻololi ʻili i ka nānā nui ʻana, ʻaʻole ia he "lāʻau lapaʻau" ma hope o ka ʻoiaʻiʻo, akā ua hoʻohui ʻia i loko o ke kaʻina hana hoʻomākaukau holoʻokoʻa, e kāohi ana i ka agglomeration mai ke kumu a hoʻomaikaʻi i ka dispersibility o ka pauka a me kona kūlike me ka ʻōnaehana noi. III. Ke Kāhea o nā Noi: Pehea e lilo ai ka nui o ka ʻāpana i ka "Photo o ka Akeakamai"?
No ke aha e hele ai i nā lōʻihi loa e kāohi i ka nui o nā ʻāpana? Ke nānā nei i nā noi hana e maopopo ai. Ma ke kahua o ka wili pololei a me ka polishing, e like me ka polishing sapphire screens a me nā wafers silicon, ʻo ka hoʻolaha ʻana o ka nui o nā ʻāpana o ka silicon carbide micro-powder ʻōmaʻomaʻo he "ala ola." Pono ia i kahi hoʻolaha nui loa a like, ʻaʻohe loa o nā "ʻāpana nui" (i kapa ʻia hoʻi ʻo "nā ʻāpana abrasive" a i ʻole "nā ʻāpana pepehi kanaka"), inā ʻaʻole hiki i kahi ʻōpala hohonu hoʻokahi ke hōʻino i ka workpiece pipiʻi holoʻokoʻa. I ka manawa like, ʻaʻole pono e loaʻa i ka pauka nā agglomerates paʻakikī, inā ʻaʻole e haʻahaʻa ka pono o ka polishing, a ʻaʻole e ʻoluʻolu ka hoʻopau ʻana o ka ʻili. Maanei, mālama pono ʻia ka kaohi ʻana o ka nui o nā ʻāpana ma ka nanoscale.
I loko o nā mea pale ʻino holomua, e like me nā lako hale umu seramika a me nā uhi umu wela kiʻekiʻe, kālele ka mana o ka nui o nā ʻāpana i ka "hoʻolaha nui o nā ʻāpana." Hoʻohui ʻia nā ʻāpana coarse a me nā ʻāpana liʻiliʻi i kahi ʻāpana; hana nā ʻāpana coarse i ke kiʻikuhi, a hoʻopiha nā ʻāpana liʻiliʻi i nā hakahaka. ʻAe kēia i ka sintering paʻa a ikaika i nā mahana kiʻekiʻe, e hopena ana i ka pale ʻana i ka haʻalulu wela maikaʻi. Inā kūpono ʻole ka hoʻolaha nui o nā ʻāpana, e porous ka mea a ʻaʻole paʻa, a palupalu paha a maʻalahi i ka haki. Ma ke kahua o nā keramika kūikawā, e like me nā keramika pale pōkā a me nā apo sila pale ʻaʻahu, pili pololei ka nui o ka ʻāpana pauka i ka microstructure a me ka hana hope loa ma hope o ka sintering. Loaʻa i nā pauka Ultrafine a me nā pauka like ka hana sintering kiʻekiʻe, e ʻae ana i ka density kiʻekiʻe a me nā keramika palaoa maikaʻi i nā mahana haʻahaʻa, no laila e hoʻomaikaʻi nui i ko lākou ikaika a me ka paʻakikī. Maanei, ʻo ka nui o nā ʻāpana ka mea huna kūloko i ka "hoʻoikaika" ʻana i ka mea keramika.