Ka wehewehe kikoʻī o ka Isostatic Pressing Graphite (2)

1.4 wili lua

Hoʻopiʻi ʻia ka pāpaʻi, ʻili ʻia, a kānana ʻia i loko o nā ʻāpana o nā ʻumi a hiki i nā haneli micrometers ka nui ma mua o ka hui like ʻana. Hoʻohana ʻia ʻo ia ma ke ʻano he mea kaomi, i kapa ʻia ka pauda kaomi. ʻO nā mea hana no ka wili lua e hoʻohana mau i ka wili wili a i ʻole ka wili pōlele.

1.5 Hoʻokumu

ʻAʻole like me ka extrusion maʻamau a me ka hoʻoheheʻe ʻana,graphite kaomi isostaticua hana ʻia me ka hoʻohana ʻana i ka ʻenehana kaomi isostatic anu (Figure 2). E hoʻopiha i ka pauda maka i loko o ka mold rubber, a hoʻopili i ka pauka ma o ka haʻalulu electromagnetic kiʻekiʻe. Ma hope o ka hoʻopaʻa ʻana, e hoʻomāmā i nā ʻāpana pauda e hoʻopau i ka ea ma waena o lākou. E kau i loko o kahi pahu kiʻekiʻe e loaʻa ana ka media wai e like me ka wai a i ʻole ka aila, e kaomi i ka 100-200MPa, a kaomi i loko o kahi huahana cylindrical a rectangular paha.

Wahi a Pascal, hoʻohana ʻia ke kaomi ʻana i kahi mole kaila ma o ka wai wai e like me ka wai, a ua like ke kaomi ma nā ʻaoʻao āpau. Ma kēia ala, ʻaʻole i kuhikuhi ʻia nā ʻāpana pauka i ka hoʻopiha piha ʻana i ka mold, akā ua hoʻopili ʻia i kahi hoʻonohonoho ʻole. No laila, ʻoiai he anisotropic ka graphite i nā waiwai crystallographic, holoʻokoʻa, ʻo ka isostatic kaomi graphite he isotropic. ʻO nā huahana i hana ʻia ʻaʻole wale nā ​​ʻano cylindrical a me nā rectangular, akā, nā ʻano cylindrical a me nā crucible.

Hoʻohana nui ʻia ka mīkini hoʻoheheʻe isostatic i ka ʻoihana metallurgy pauka. Ma muli o ke koi ʻana o nā ʻoihana kiʻekiʻe e like me ka aerospace, ka ʻoihana nuklea, nā alloys paʻakikī, a me nā electromagnetic kiʻekiʻe-voltage, wikiwiki loa ka hoʻomohala ʻana o ka ʻenehana isostatic kaomi, a hiki iā ia ke hana i nā mīkini hoʻoheheʻe isostatic anuanu me kahi cylinder hana. ʻO ke anawaena o loko o 3000mm, ke kiʻekiʻe o 5000mm, a me ke kaomi hana kiʻekiʻe o 600MPa. I kēia manawa, ʻo Φ 2150mm × 4700mm nā kikoʻī kiʻekiʻe loa o nā mīkini paʻi isostatic i hoʻohana ʻia i ka ʻoihana kalapona no ka hana ʻana i ka isostatic pressing graphite he Φ 2150mm × 4700mm, me ke kaomi hana kiʻekiʻe o 180MPa.

1.6 Bakina

I loko o ke kaʻina hoʻoheheʻe ʻana, hiki mai kahi hopena kemika paʻakikī ma waena o ka mea hoʻohui a me ka mea hoʻopili, e hoʻoheheʻe ʻia ka mea hoʻopaʻa a hoʻokuʻu i ka nui o nā mea hoʻoheheʻe, ʻoiai ke komo pū nei i kahi hopena condensation. I ka haʻahaʻa haʻahaʻa preheating pae, hoʻonui ka hua maka ma muli o ka hoʻomehana ʻana, a ma ke kaʻina hana hoʻomehana aʻe, emi ka leo ma muli o ka hopena condensation.

ʻO ka nui o ka nui o ka huahana maka, ʻoi aku ka paʻakikī o ka hoʻokuʻu ʻana i nā mea volatile, a ʻo ka ʻili a me loko o ka huahana maka e maʻalahi i nā ʻokoʻa wela, ka hoʻonui ʻole ʻana o ka wela a me ka ʻokiʻoki, hiki ke alakaʻi i nā māwae o ka huahana maka.

Ma muli o kona ʻano maikaʻi, pono ka graphite kaomi isostatic i kahi kaʻina hoʻoheheʻe lohi, a ʻo ka mahana o loko o ka umu e ʻaʻahu loa, ʻoi aku hoʻi i ka wā wela kahi e hoʻokuʻu koke ʻia ai nā asphalt volatiles. Pono e hoʻokō ʻia ke kaʻina hana hoʻomehana me ka akahele, me ka helu wela ʻaʻole iʻoi aku ma mua o 1 ℃/h a me kahi ʻokoʻa wela i loko o ka umu ma lalo o 20 ℃. ʻO kēia kaʻina hana ma kahi o 1-2 mahina.

1.7 Impregnation

I ka wā e kālua ʻia ai, hoʻokuʻu ʻia ka mea maʻalahi o ka pitch tar lanahu. Ua waiho ʻia nā pores maikaʻi i loko o ka huahana i ka wā o ka hoʻokuʻu ʻana o ke kinoea a me ka hoʻohaʻahaʻa ʻana i ka leo, aneane pau nā pores hāmama.

I mea e hoʻomaikaʻi ai i ka nui o ka leo, ikaika mechanical, conductivity, thermal conductivity, a me ke kūʻē kemika o ka huahana, hiki ke hoʻohana ʻia ke ʻano o ka impregnation pressure, e pili ana i ka impregnating coal tar pitch i loko o ka huahana ma o nā pores hāmama.

Pono e hoʻomaʻamaʻa mua ʻia ka huahana, a laila holoi ʻia a hoʻohemo ʻia i loko o ka pahu impregnation. A laila, hoʻohui ʻia ka asphalt tar i hoʻoheheʻe ʻia i ka pahu impregnation a kaomi ʻia e ʻae i ka asphalt agent impregnating e komo i loko o ka huahana. ʻO ka maʻamau, ʻo ka isostatic pressing graphite e loaʻa i nā pōʻai he nui o ka impregnation roasting.

1.8 Kiʻi kiʻi

E hoʻomaʻamaʻa i ka huahana calcined ma kahi o 3000 ℃, e hoʻonohonoho i ka lattice o nā ʻātoma kalapona ma ke ʻano kūpono, a hoʻopau i ka hoʻololi ʻana mai ke kalapona i ka graphite, i kapa ʻia ʻo graphitization.

ʻO nā ʻano hana kiʻi kiʻi e pili ana i ke ʻano Acheson, ke ʻano hoʻohui wela i loko, ke ʻano induction kiʻekiʻe, a me nā mea ʻē aʻe. Hiki i kēlā me kēia umu ahi ke lawelawe i nā tona a hiki i nā kakini o nā huahana i kālua ʻia.