Thaum siv cov ntaub ntawv refractory, lawv tau yooj yim yaj thiab softened los ntawm lub cev, tshuaj, mechanical thiab lwm yam teebmeem ntawm qhov kub thiab txias (feem ntau 1000 ~ 1800 ° C), los yog eroded los ntawm yaig, los yog tawg thiab puas, uas cuam tshuam kev lag luam. Cov khoom tsis huv. Yog li, nws yuav tsum tau hais tias cov khoom siv refractory yuav tsum muaj cov khoom uas tuaj yeem hloov mus rau ntau yam kev ua haujlwm. Cov hauv qab no yog 4 qhov ntsuas uas txiav txim siab qhov kub thiab txias ntawm cov khoom siv refractory:
(1) Refractoriness
Refractoriness yog hais txog qhov kub thiab txias ntawm cov khoom siv mus txog qhov tshwj xeeb ntawm softening nyob rau hauv qhov kev txiav txim ntawm qhov kub thiab txias, thiab characterizes qhov kev ua tau zoo ntawm cov khoom tiv thaiv kub kub. Refractoriness yog lub hauv paus rau kev txiav txim seb cov khoom puas tuaj yeem siv los ua refractory. Lub Koom Haum Thoob Ntiaj Teb rau Standardization tau teev tseg tias cov khoom siv tsis muaj hlau tsis muaj hlau nrog refractoriness saum 1500 ℃ yog cov khoom siv refractory. Nws yog qhov sib txawv ntawm qhov melting point ntawm cov khoom siv thiab yog cov lus qhia dav dav ntawm kev sib xyaw ntawm cov khoom sib txawv ntawm cov khoom sib txawv uas muaj ntau yam minerals.
Qhov tseem ceeb tshaj plaws uas txiav txim siab txog qhov refractoriness yog cov tshuaj ntxhia hauv cov khoom sib xyaw thiab faib cov khoom. Ntau yam impurity Cheebtsam, tshwj xeeb tshaj yog cov uas muaj zog hnyav hnyav, yuav txo tau cov refractoriness ntawm cov khoom. Yog li ntawd, kev ntsuas tsim nyog yuav tsum tau txiav txim siab hauv cov txheej txheem tsim khoom los xyuas kom meej thiab txhim kho cov purity ntawm cov khoom siv raw.
Refractoriness tsis yog lub cev muaj nuj nqis tshwj xeeb rau ib yam khoom, tab sis tus txheeb ze kev qhia thaum cov khoom mus txog qhov tshwj xeeb softening degree ntsuas raws li cov kev sim tshwj xeeb. Cov khoom siv kuaj tau ua rau hauv lub khob hliav qab lub khob hliav qab (xa mus rau lub khob ntsuas lub khob) raws li cov txheej txheem sau tseg, thiab tus qauv truncated triangular cone (hu ua tus qauv lub khob hliav qab) nrog rau qhov ntsuas kub ntawm qhov ntsuas kub tshwj xeeb. Cua sov, thiab cov refractoriness yog txiav txim los ntawm kev sib piv cov degree ntawm dabtsi yog khoov ntawm lub khob hliav qab xeem nrog rau cov degree ntawm dabtsi yog khoov ntawm tus qauv cone. Qhov qis hauv qab ntawm lub khob hliav qab yog 8 hli ntev ntawm txhua sab, sab sauv yog 2 hli ntawm txhua sab, thiab qhov siab yog 30 hli. Thaum lub sij hawm ntsuas, ib theem kua yuav tshwm nyob rau hauv lub pyramid ntawm qhov kub thiab txias. Raws li qhov kub thiab txias, cov kua theem nce, lub viscosity ntawm cov kua theem txo, thiab lub khob hliav qab softens. Thaum cov softening nce mus txog ib theem, lub khob hliav qab maj khoov vim nws qhov hnyav. Thaum lub khob ntsuas lub khob thiab lub khob ntim tau khoov tib lub sijhawm kom txog rau thaum lawv lub apex nyob rau hauv kev sib cuag nrog lub chassis, qhov ntsuas kub ntawm lub khob hliav qab yuav tsum yeej raws li qhov refractoriness ntawm lub khob ntsuas.
Kuj tseem hu ua qhov muag muag ntawm refractory nyob rau hauv load lossis deformation kub ntawm refractory nyob rau hauv load, nws qhia tau hais tias qhov kev tiv thaiv ntawm refractory rau kev ua ke ntawm kub kub thiab load nyob rau hauv tas li load los yog kub ntau yam nyob rau hauv uas refractory exhibits pom tseeb yas deformation. Qhov siab tshaj plaws kev pab cuam kub ntawm lub refractory yuav inferred los ntawm softening kub nyob rau hauv load. Lub softening kub nyob rau hauv load sawv cev rau lub structural zog ntawm lub refractory nyob rau hauv zoo xws li cov kev siv, thiab yuav siv tau raws li lub hauv paus rau kev txiav txim siab qhov siab tshaj plaws kev pab cuam kub ntawm lub refractory.
Qhov tseem ceeb tshaj plaws uas txiav txim siab qhov kub thiab txias nyob rau hauv kev thauj khoom yog cov tshuaj ntxhia hauv cov khoom siv, uas tseem cuam tshuam ncaj qha rau cov txheej txheem tsim khoom ntawm cov khoom. Lub sintering kub ntawm cov khoom muaj kev cuam tshuam zoo rau lub softening deformation kub nyob rau hauv load. Yog hais tias qhov kub ntawm sintering yog tsim nyog, qhov pib deformation kub yuav nce vim qhov txo qis ntawm porosity, kev loj hlob ntawm cov muaju, thiab kev sib txuas zoo. Kev txhim kho cov purity ntawm raw cov ntaub ntawv thiab txo cov ntsiab lus ntawm tsawg yaj los yog hnyav yuav ua rau kom lub softening deformation kub nyob rau hauv load. Piv txwv li, sodium oxide nyob rau hauv av nplaum cib thiab alumina nyob rau hauv silica bricks yog tag nrho cov teeb meem oxides.
(3) Kev kub siab ntim ruaj khov ntawm cov ntaub ntawv refractory
Nyob rau hauv qhov kev txiav txim ntawm qhov kub thiab txias rau lub sijhawm ntev, cov khoom siv refractory tsim ntim nthuav dav, uas yog hu ua residual expansion. Qhov loj ntawm qhov seem nthuav dav (deformation) ntawm cov khoom siv refractory qhia txog qhov zoo ntawm qhov kub siab ntim ruaj khov. Qhov me dua qhov seem deformation, qhov zoo dua qhov ntim stability; ntawm qhov tsis sib xws, qhov tsis zoo ntawm qhov ntim ruaj khov, qhov yooj yim dua nws ua rau deformation lossis kev puas tsuaj ntawm cov masonry.
Kev hloov ntawm cov kab rov ua dua yog feem ntau siv los txiav txim siab qhov kub siab ntim ruaj khov ntawm cov khoom siv, uas yog qhov tseem ceeb rau kev ntsuas qhov zoo ntawm cov khoom.
Feem ntau cov ntaub ntawv refractory yuav shrink nyob rau hauv qhov kev txiav txim siab kub. Thaum lub sij hawm refractory, feem ntau cov ntaub ntawv refractory yuav ntsws, feem ntau vim hais tias cov kua theem generated los ntawm cov khoom nyob rau hauv high kub yuav sau lub pores, thiaj li hais tias cov particles yog ntxiv nruj nreem thiab rub tsis ntev los no, recrystallization tshwm sim, ua rau ntxiv densification ntawm cov khoom. Kuj tseem muaj ob peb cov ntaub ntawv uas nthuav dav thaum rov ua dua. Piv txwv li, silica cib nthuav vim polycrystalline transformation thaum siv. Qhov no yog vim qhov tsis hloov pauv quartz ntawm silica cib yuav txuas ntxiv hloov mus rau hauv tridymite lossis square ntawm qhov kub siab. Quartz, uas nthuav dav hauv ntim, yog li 10% tsis hloov pauv hauv silica cib. Txhawm rau txo qhov rov ua kom tawg thiab nthuav dav ntawm cov khoom siv, nws yog qhov tsim nyog los ua kom qhov kub thiab txias thiab ua kom lub sijhawm tuav, tab sis nws yuav tsum tsis txhob siab dhau, txwv tsis pub nws yuav ua rau cov khoom siv vitrification thiab txo. thermal shock stability. Vim tias qhov nthuav dav ntawm cov khoom siv quartz hauv cov khoom siv thaum tua hluav taws thiab siv, uas ua rau lub shrinkage ntawm av nplaum, lub ntim hloov ntawm semi-silica bricks yog me me, thiab qee qhov ntawm lawv yog me ntsis nthuav.
(4) Thermal shock stability
Lub peev xwm ntawm refractories los tiv thaiv kev hloov pauv sai hauv qhov kub tsis muaj kev puas tsuaj yog hu ua thermal shock stability. Cov cuab yeej no tseem hu ua thermal shock resistance lossis thermal shock resistance.
Lub ntsiab tseem ceeb cuam tshuam rau thermal shock stability Performance index ntawm cov khoom yog lub cev lub cev ntawm cov khoom, xws li thermal expansion, thermal conductivity thiab thiaj li nyob. Feem ntau hais lus, qhov siab dua qhov kev nthuav dav ntawm cov khoom siv, qhov tsis zoo ntawm thermal shock stability; qhov siab dua cov thermal conductivity ntawm cov khoom, qhov zoo dua thermal shock stability. Tsis tas li ntawd, microstructure, particle muaj pes tsawg leeg thiab cov duab ntawm cov khoom siv refractory tag nrho muaj kev cuam tshuam rau thermal shock stability.
Post lub sij hawm: Lub Xya hli ntuj-15-2022