Low Cement Refractory Castable Product Introduction

Otsika simenti refractory castables poyerekeza ndi miyambo aluminiyamu simenti refractory castables. Kuchuluka kwa simenti kumapangidwe amtundu wa aluminate simenti refractory nthawi zambiri kumakhala 12-20%, ndipo kuchuluka kwa madzi nthawi zambiri kumakhala 9-13%. Chifukwa cha kuchuluka kwa madzi owonjezera, thupi loponyedwa lili ndi pores ambiri, silili wandiweyani, ndipo lili ndi mphamvu zochepa; chifukwa cha kuchuluka kwa simenti anawonjezera, ngakhale apamwamba zachibadwa ndi otsika kutentha mphamvu angapezeke, mphamvu amachepetsa chifukwa crystalline kusintha kwa calcium aluminate pa sing'anga kutentha. Mwachiwonekere, CaO yoyambitsidwayo imagwira ntchito ndi SiO2 ndi Al2O3 muzoponyera kuti apange zinthu zotsika zosungunuka, zomwe zimapangitsa kuwonongeka kwa kutentha kwa zinthuzo.

Mukamagwiritsa ntchito ukadaulo wa ufa wa ultrafine, ma admixtures apamwamba kwambiri komanso kuphatikizika kwa tinthu tating'ono ta sayansi, zinthu za simenti zomwe zimaponyedwa zimachepetsedwa mpaka 8% ndipo madziwo amachepetsedwa mpaka ≤7%, ndipo gawo lotsika la simenti lotayirira limatha kukhala. zokonzedwa ndi kubweretsedwa mu CaO zili ndi ≤2.5%, ndipo zizindikiro zake zimaposa za aluminate zotayira simenti. Mtundu uwu wa refractory castable uli ndi thixotropy wabwino, ndiko kuti, zinthu zosakanikirana zimakhala ndi mawonekedwe enaake ndipo zimayamba kuyenda ndi mphamvu yakunja. Mphamvu yakunja ikachotsedwa, imasunga mawonekedwe opezeka. Choncho, amatchedwanso thixotropic refractory castable. Self-othamanga refractory castable amatchedwanso thixotropic refractory castable. Ndi wa gulu ili. Tanthauzo lenileni la otsika simenti mndandanda refractory castables sanafotokoze mpaka pano. Bungwe la American Society for Testing and Equipment (ASTM) limatanthauzira ndikuyika m'magulu osakanizidwa motengera zomwe zili mu CaO.

Wandiweyani ndi mkulu mphamvu ndi mbali zabwino za otsika simenti mndandanda refractory castables. Izi ndi zabwino pakuwongolera moyo wautumiki ndi magwiridwe antchito azinthu, komanso zimabweretsa zovuta pakuphika musanagwiritse ntchito, ndiye kuti, kuthira kumatha kuchitika mosavuta ngati simusamala pakuphika. Chochitika cha kuphulika kwa thupi chingafunike kutsanuliranso pang'ono, kapena chikhoza kuyika pangozi chitetezo chaumwini cha ogwira ntchito ozungulira pazochitika zazikulu. Choncho, mayiko osiyanasiyana achititsanso maphunziro osiyanasiyana pa kuphika kwa otsika simenti mndandanda refractory castables. Njira zazikuluzikulu zaukadaulo ndi izi: popanga ma curve oyenerera ovuni ndikuyambitsa zida zabwino zothana ndi kuphulika, ndi zina zambiri, izi zitha kupangitsa kuti ma refractory castables Madzi achotsedwe bwino popanda kuyambitsa zovuta zina.

Ukadaulo wa ufa wa Ultrafine ndiye ukadaulo wofunikira kwambiri wazitsulo zotsika za simenti (pakali pano mitundu yambiri ya ufa wa ultrafine yomwe imagwiritsidwa ntchito muzoumba ndi zinthu zowumbitsirana kwenikweni imakhala pakati pa 0.1 ndi 10m, ndipo imagwira ntchito ngati ma accelerator omwazikana ndi ma densifiers apangidwe. . simenti particles kwambiri omwazika popanda flocculation, pamene chotsirizira amapanga micropores mu kuthira thupi mokwanira wodzazidwa ndi bwino mphamvu.

Pakali pano mitundu yodziwika bwino ya ufa wa ultrafine ikuphatikizapo SiO2, α-Al2O3, Cr2O3, ndi zina zotero. kudzaza katundu. Kuphatikiza apo, SiO2, Al2O3, Cr2O3 micropowder, ndi zina zambiri zimatha kupanga tinthu tating'onoting'ono m'madzi. Pamene dispersant alipo, ndi akuthwana magetsi iwiri wosanjikiza aumbike pamwamba pa particles kupanga electrostatic repulsion, amene akugonjetsa van der Waals mphamvu pakati particles ndi kumachepetsa mawonekedwe mphamvu. Zimalepheretsa kutengeka ndi kuyandama pakati pa tinthu tating'onoting'ono; nthawi yomweyo, dispersant ndi adsorbed kuzungulira particles kupanga zosungunulira wosanjikiza, amenenso kumawonjezera fluidity wa castable. Ichi ndi chimodzi mwa njira za ufa wa ultrafine, ndiko kuti, kuwonjezera ufa wa ultrafine ndi dispersants oyenerera akhoza kuchepetsa kumwa kwa madzi a refractory castables ndikuwongolera fluidity.

Kukhazikitsa ndi kuumitsa kwazitsulo zochepetsera simenti zotsika ndi zotsatira za kuphatikizika kwa hydration bonding ndi cohesion bonding. Ma hydration ndi kuumitsa kwa simenti ya calcium aluminate makamaka ndi hydration ya magawo a hydraulic CA ndi CA2 ndi kukula kwa kristalo kwa ma hydrates awo, ndiko kuti, amachitira ndi madzi kuti apange hexagonal flake kapena singano CAH10, C2AH8 ndi Hydration mankhwala monga monga makhiristo a C3AH6 ndi ma gels a Al2O3аq kenako amapanga mawonekedwe olumikizana a condensation-crystallization network panthawi yochiritsa ndi kutentha. The agglomeration ndi kugwirizana ndi chifukwa yogwira SiO2 ultrafine ufa kupanga colloidal particles akakumana ndi madzi, ndipo amakumana ndi ayoni pang'onopang'ono dissociated kuchokera anawonjezera zowonjezera (ie electrolyte mankhwala). Chifukwa chakuti pamwamba paziwirizi ndi zotsutsana, ndiko kuti, pamwamba pa colloid ili ndi ma adsorbed counter ions, zomwe zimapangitsa kuti £ 2 Kuthekera kumachepa ndipo condensation imachitika pamene adsorption ifika pa "isoelectric point". M'mawu ena, pamene electrostatic repulsion pamwamba pa particles colloidal ndi zosakwana kukopa ake, cohesive kugwirizana kumachitika mothandizidwa ndi van der Waals mphamvu. Pambuyo refractory castable wosakanizidwa ndi silika ufa ndi condensed, magulu Si-OH opangidwa pamwamba pa SiO2 zouma ndi kutaya madzi mlatho, kupanga siloxane (Si-O-Si) maukonde dongosolo, potero kuumitsa. Mu mawonekedwe a netiweki ya siloxane, zomangira pakati pa silicon ndi okosijeni sizimachepera pomwe kutentha kumawonjezeka, kotero mphamvu imapitilirabe kukula. Panthawi imodzimodziyo, pa kutentha kwakukulu, mawonekedwe amtundu wa SiO2 adzachitapo kanthu ndi Al2O3 atakulungidwa mmenemo kuti apange mullite, yomwe ingapangitse mphamvu pa kutentha kwapakati ndi kutentha.