He aha nā pōhaku paʻa i hoʻohana ʻia i loko o nā umu hoʻomehana? He alakaʻi piha

ʻO nā piliki ahi nā piliki refractory kumu i hoʻohana nui ʻia i nā umu hoʻomehana. Hana ʻia mai kaolin me kahi o30% Al₂O₃, hōʻike lākou i ke kūpaʻa haʻalulu wela maikaʻi loa a me ke kumukūʻai haʻahaʻa, e kūpono ana iā lākou no nā wahi mahana waena(1200–1400℃)e like me nā paia umu, nā ʻauwai, a me nā luna umu haʻahaʻa. ʻO ko lākou kūpaʻa wela maikaʻi e pale aku i ka haki ʻana mai nā loli wikiwiki o ka mahana, ʻoiai ʻo ko lākou kumukūʻai kūpono e kōkua i ka kaohi ʻana i nā kumukūʻai papahana holoʻokoʻa, e lilo ana lākou i koho kūpono no nā umu ʻoihana maʻamau.

ʻO nā piliki alumina kiʻekiʻe he mau koho ʻē aʻe i hoʻonui ʻia i nā piliki fireclay, aia ma luna o48% Al₂O₃Me ke kūpaʻa kiʻekiʻe(1400–1600℃), ʻoi aku ka ikaika o ka compressive, a me ka pale ʻana i ka erosion, kūpono lākou no nā ʻāpana ukana wela kiʻekiʻe e like me nā uhi umu, nā luna umu, a me nā puka umu. Hoʻokaʻawale ʻia e ka nui o Al₂O₃, hoʻokō lākou i nā koi mahana like ʻole, e hoʻohana nui ʻia ai i nā umu hoʻomehana metallurgical a me nā kemika kahi e pono ai ke kūpaʻa wela kiʻekiʻe.

Nā pōhaku lepo silica, meʻOi aku ka nui o ka SiO₂ ma mua o 94%, ʻoi aku ka maikaʻi ma ke kūpaʻa o ka leo wela kiʻekiʻe, me ka mahana palupalu o ka ukana ma luna o1650℃Hoʻohana nui ʻia lākou i nā ʻāpana wela loa e like me nā luna umu a me nā mea hoʻoulu hou, ʻoi aku hoʻi i nā lewa umu oxidizing. Eia nō naʻe, ʻo ko lākou kūpaʻa haʻalulu wela haʻahaʻa e kaupalena i kā lākou hoʻohana ʻana i nā wahi me nā loli pinepine o ka mahana.

Ua hoʻolālā ʻia nā piliki paʻakikī alkaline, me nā piliki magnesia a me nā piliki magnesia-alumina, no nā ʻano ʻino. ʻO nā piliki magnesia, i hana nui ʻia meMgO, hiki ke kū i nā mahana a hiki i2000℃a he kūpaʻa ikaika i ka slag alkaline, e kūpono ai no nā lalo umu a me nā laina slag i ka launa pū ʻana me nā melts alkaline. Hoʻomaikaʻi nā piliki Magnesia-alumina i ke kūpaʻa haʻalulu wela ma ka hoʻohui ʻana i ka alumina, e hoʻololi ana i nā kūlana hana paʻakikī.

Nā piliki paʻa kūikawā e like me nā piliki corundum(Al₂O₃ ≥90%)a hoʻohana ʻia nā piliki silicon carbide no nā ʻāpana koʻikoʻi. Kūʻē nā piliki Corundum i nā mahana ma luna1800℃a kūpono hoʻi no nā wahi i hōʻike pololei ʻia i nā lapalapa ahi a i ʻole ka ʻino nui o ka slag. Hāʻawi nā piliki silikona carbide i ke kūpaʻa maikaʻi loa i ka ʻaʻahu a me ke kūpaʻa ʻana i ka haʻalulu wela, kūpono no nā lalo o ka umu, nā lua ahi, a me nā ʻāpana ʻē aʻe i ʻaʻahu nui ʻia.