Kedu ihe bụ corundum?

Corundum (Al2O3) nwere nnukwu ihe nchekwa akụrụngwa, na-aza ihe dịka 25% nke ịdị arọ nke jikọrọ ọnụ ụwa. Ọ dị ọnụ ala ma nwee ọtụtụ ihe mara mma. Enwere ọtụtụ kristal dị iche iche nke Al2O3, ma enwere ihe karịrị ụdị iri dị iche iche akọwara, mana enwere isi atọ, ya bụ α-Al2O3, β-Al2O3, na γ-Al2O3.

Corundum tabular

γ-Al2O3 bụ usoro ọkpụkpụ azụ, nke na-adịghị akwụsi ike na oke okpomọkụ ma na-adịkarịghị eji dị ka otu ihe. β-Al2O3 bụ n’ezie ihe aluminate nwere alkali ọla ma ọ bụ alkaline ụwa ọla. Ya chemical mejupụtara nwere ike ịdị nso site RO · 6Al2O3 na R2O · 11Al2O3, hexagonal lattice, density 3.30 ~ 3.63g / cm3, 1400 ~ 1500 Ọ na-amalite decompose na ℃ na-agbanwe n’ime α-Al2O3 na 1600. α-Al2O3 bụ ụdị okpomọkụ dị elu, nke nwere okpomọkụ siri ike dị elu dị ka ebe mgbaze, na njupụta nke 3.96 ~ 4.01g / cm3, nke metụtara ọdịnaya adịghị ọcha. The unit cell bụ prism dị nkọ, nke dị n’ụdị corundum eke, ruby na sapphire na okike. α-Al2O3 nwere nhazi kọmpat, ọrụ dị ala, akụrụngwa eletrik dị mma, yana akụrụngwa akụrụngwa dị mma. The Mohs hardness bụ 9. α-Al2O3 bụ nke hexagonal crystal usoro, corundum Ọdịdị, a = 4.76, c=12.99.

Al2O3 nwere nnukwu ígwè ọrụ ike. Ihe mejupụtara Al2O3 dị ọcha, ka ike dị elu. Enwere ike iji ike arụ ọrụ mee poselin ngwaọrụ na ihe ndị ọzọ na-arụ ọrụ. Nguzogide nke Al2O3 dị elu, ọrụ mkpuchi ọkụ eletrik dị mma, ihe mgbochi na ụlọ okpomọkụ bụ 1015Ω · cm, ike dielectric bụ 15kV / mm. N’iji mkpuchi ya na ike ya, enwere ike ime ya n’ime ihe ndị dị na ya, sọks, ọkụ ọkụ, shells sekit, wdg Al2O3 nwere ike siri ike, Mohs hardness nke 9, gbakwunyere magburu onwe ya na-eguzogide, n’ihi ya, a na-eji ya eme ihe na-emepụta ngwá ọrụ, igwe na-egweri. abrasives, ịbịaru anwụ, bearings, na-ebu bushes na wuru ewu. Al2O3 nwere ebe mgbaze dị elu na nguzogide corrosion. Ọ nwere ebe mgbaze nke 2050 ° C. Ọ nwere ezigbo nguzogide nbibi nke ọla a wụrụ awụ dị ka Be, Sr, Ni, Al, V, Ti, Mn, Fe, CO na sodium hydroxide, iko, na slag. Ọ nwekwara nnukwu nguzogide; ọ naghị emekọrịta ihe na Si, P, Sb, Bi na ikuku inert, yabụ enwere ike iji ya dị ka ihe mgbagha, ọkpọkọ ọkụ, ihe osise iko, bọọlụ oghere, eriri na mkpuchi mkpuchi thermocouple, wdg.

Al2O3 nwere ezigbo nkwụsi ike kemịkalụ. Ọtụtụ sulfide dị mgbagwoju anya, phosphides, arsenides, chlorides, nitrides, bromides, iodides, fluorides akọrọ, sulfuric acid, hydrochloric acid, nitric acid na hydrofluoric acid adịghị emekọrịta ihe na Al2O3. Ya mere, ọ nwere ike mee ka ọ bụrụ metal dị ọcha na otu kristal ibu crucibles, nkwonkwo mmadụ, ọkpụkpụ artificial, wdg Al2O3 nwere ngwa anya ihe onwunwe na ike na-eme ka ìhè-ebunye ihe na-eme ka Na vapor oriọna tubes, ngwa ndakwa nri fairings, infrared windo na laser. akụkụ oscillation. A na-eji ionic conductivity nke Al2O3 mee ihe dị ka ihe maka sel anyanwụ na batrị nchekwa. A na-ejikwa Al2O3 na teknụzụ n’elu seramiiki metallization.

Akụkụ bụ isi kristal nke corundum fused alumina bụ usoro corundum nwere nha nke 1.0-1.5mm na kristal jikọtara ọnụ. Ndị ọzọ bụ ọnụọgụ nke rutile, alumina na aluminom titanate, ma dị n’ime usoro corundum ma ọ bụ n’etiti usoro kristal. Obere oge nke iko iko. Na China, mgbe ihe karịrị afọ iri nke mgbalị na-adịghị akwụsị akwụsị, usoro mgbaze nke corundum fused bauxite nwere ọganihu dị ukwuu, na-enwe ike ịmepụta ihe karịrị tọn 110,000 kwa afọ. Corundum fused dabeere na Bauxite ejirila nke ọma mee ihe dị ka akụrụngwa maka brik dị iche iche a chụpụrụ na ihe mgbagha enweghị ọdịdị. Dịka ọmụmaatụ, ọ nwere ike dochie corundum siri ike na nkedo ọkụ ọkụ, a na-ejikwa ya dị ka ihe matriks na ihe granular na-emepụta ihe na-adịghị ala ala. A na-eji brik alumina dị elu dochie corundum ọcha na ndị ọzọ Al2O3-SiO2 refractories iji kwadebe ngwaahịa dị elu.

Brown corundum smelting dabeere na isi ụkpụrụ na aluminum nwere affinity ka ukwuu maka oxygen karịa ígwè, silicon, titanium, wdg Site ịchịkwa ego nke mbenata gị n’ụlọnga, isi adịghị ọcha na bauxite na-ebelata site Mbelata smelting, na mbelata adịghị ọcha na-etolite. ferrosilicon alloys. A na-ekewapụ ya na corundum gbazee iji nweta corundum aja aja na àgwà kristal na-ezute ihe achọrọ na ọdịnaya Al2O3 karịa 94.5%. Fe2O3 na-ebelata iji mepụta ferrosilicon alloy ma wepụ ya n’oge usoro ịgbaze, ma a ka na-ahapụ obere ígwè oxide na alumina na-emepụta spinel na ngwaahịa ahụ. A na-ebelata TiO2 n’ime akụkụ ferrosilicon alloy n’oge usoro ịgbaze, na akụkụ dị ukwuu nke ya na-anọgide na corundum agba aja aja, bụ isi ihe na-eme ka agba agba nke corundum aja aja. CaO na MgO siri ike ibelata n’oge usoro mgbaze, na ọtụtụ n’ime CaO na MgO na akụrụngwa ka dị na ngwaahịa. Ọ bụ ezie na Na2O na K2O nwere ike ịmegharị na okpomọkụ dị elu n’oge usoro ịgbaze, ha enweghị ike ibelata ma nọgide na corundum agba aja aja, nke nwere mmetụta dị ukwuu na àgwà.

Brown corundum

Ngwakọta nke corundum agba aja aja bụ ọka α-alumina kristal na obere obere iko, kristal α-alumina bụ nke ihe ngwọta siri ike nke Al2O3 nwere Ti2O3, na oge iko na-abụkarị titanium dioxide na silicon dioxide na ndị ọzọ. Chọpụta oxidation dị na ọkụ ọkụ arc eletrik. 物组合。 Ihe mejupụtara ya. Ihe ndị a oxides mejupụtara oge iko, na ha nwere naanị obere solubility na nhazi kristal nke ọka alumina. Ti2O3 bụ naanị oxide nke Ti nwere ike igbari na ọka alumina. TiO2 bụ oxide kwụsiri ike nke Ti. N’oge agbaze na mbelata corundum aja aja, akụkụ nke TiO2 na-ebelata ka ọ bụrụ oxidation nke titanium. (Ti2O3), n’elu 1000 ℃, oxygen nwere ike gbasaa n’ime Ga-alumina grains, oxidize Ti2O3 n’ime ọzọ kwụsie ike TiO2 wee kechie ya na α-alumina grains, otú ọtụtụ n’ime titanium dioxide bụ α-alumina A siri ike ngwọta nke crystal. ọka dị.

The oke TiO2 na agba aja aja corundum enweghị ike ịnọgide na iko oge, ma na-emeghachi omume na alumina na-etolite aluminum titanate (TiO2 · Al2O3). Aluminium titanate bụ akụkụ nke atọ na interface n’etiti α-alumina grains na iko iko; Isi ike nke corundum aja aja na-abawanye site na uto nke kristal TiO2. Usoro TiO2 gbasasịrị n’otu n’otu na ọka kristal α-alumina na-eme ka ahụ α-alumina sie ike. Ihe ngwọta siri ike nke Brown corundum Ti2O3 na-eme ka corundum agba aja pụta na-acha anụnụ anụnụ.

Ti2O3 bụ naanị oxide nke Ti nwere ike igbari na ọka alumina. TiO2 bụ oxide kwụsiri ike nke Ti. N’oge agbaze na mbelata corundum aja aja, akụkụ nke TiO2 na-ebelata ka ọ bụrụ oxidation nke titanium. (Ti2O3), n’elu 1000 ℃, oxygen nwere ike gbasaa n’ime Ga-alumina grains, oxidize Ti2O3 n’ime ọzọ kwụsie ike TiO2 wee kechie ya na α-alumina grains, otú ọtụtụ n’ime titanium dioxide bụ α-alumina A siri ike ngwọta nke crystal. ọka dị. The oke TiO2 na agba aja aja corundum enweghị ike ịnọgide na iko oge, ma na-emeghachi omume na alumina na-etolite aluminum titanate (TiO2 · Al2O3). Aluminium titanate bụ akụkụ nke atọ na interface n’etiti α-alumina grains na iko iko; Isi ike nke corundum aja aja na-abawanye site na uto nke kristal TiO2. Usoro TiO2 gbasasịrị n’otu n’otu na ọka kristal α-alumina na-eme ka ahụ α-alumina sie ike. Ihe ngwọta siri ike nke Brown corundum Ti2O3 na-eme ka corundum agba aja pụta na-acha anụnụ anụnụ.