I-samente ephantsi ye-refractory castables ifaniswa ne-aluminem ye-cement refractory castables. Isixa esongeziweyo sesamente kwizinto ezirhangqekayo zesamente yealuminiyamu yesiqhelo idla ngokuba yi-12-20%, kwaye isixa sokongeza amanzi siqhele ukuba yi-9-13%. Ngenxa yobuninzi bamanzi abongeziweyo, umzimba otyhidiweyo unama-pores amaninzi, awunzima, kwaye unamandla aphantsi; ngenxa yobuninzi besamente eyongeziweyo, nangona amandla aphezulu aqhelekileyo kunye aphantsi okushisa anokufumaneka, amandla ayancipha ngenxa yokuguqulwa kwekristalline ye-calcium aluminate kumaqondo aphakathi. Ngokucacileyo, i-CaO eyaziswayo isabela kunye ne-SiO2 kunye ne-Al2O3 kwindawo yokuphosa ukuvelisa izinto ezisezantsi zokunyibilika, okukhokelela ekuhleni kweempawu zobushushu obuphezulu bemathiriyeli.
Xa iteknoloji ye-ultrafine powder, i-admixtures ephezulu kunye ne-particle gradation isetyenzisiweyo, umxholo we-samente we-castable uyancipha ube ngaphantsi kwe-8% kwaye umxholo wamanzi uyancitshiswa ukuya kwi-≤7%, kunye ne-sement ephantsi ye-cement refractory castable. ilungiswe yaza yangeniswa kumxholo weCaO ngu ≤2.5%, kwaye izalathisi zayo zokusebenza ngokubanzi zigqithise ezo ze-aluminate cement refractory castables. Olu hlobo lwe-refractory castable lune-thixotropy enhle, oko kukuthi, izinto ezixubileyo zinemilo ethile kwaye ziqala ukuhamba ngamandla amancinci angaphandle. Xa amandla angaphandle esusiwe, igcina imilo efunyenweyo. Ke ngoko, ikwabizwa ngokuba yi-thixotropic refractory castable. I-self-flowing refractory castable ikwabizwa ngokuba yi-thixotropic refractory castable. Ngowolu didi. Intsingiselo echanekileyo yoluhlu oluphantsi lwe-samente ye-refractory castables ayichazwanga ngoku. I-American Society for Testing and Materials (ASTM) ichaza kwaye ihlukanise ii-refractory castables ngokusekelwe kumxholo weCaO.
I-Dense kunye namandla aphezulu zizinto ezibalaseleyo ze-samente ephantsi ye-refractory castables. Oku kulungele ukuphucula ubomi benkonzo kunye nokusebenza kwemveliso, kodwa kuzisa iingxaki ekubhakeni ngaphambi kokusetyenziswa, oko kukuthi, ukugalela kunokwenzeka ngokulula ukuba awuqapheli ngexesha lokubhaka. Isenzeko sokugqabhuka komzimba sinokufuna ukugalelwa kwakhona ubuncinci, okanye sinokubeka emngciphekweni ukhuseleko lobuqu lwabasebenzi abangqongileyo kwiimeko ezinzima. Ke ngoko, amazwe ahlukeneyo aqhube amaphononongo ahlukeneyo malunga nokubhakwa kothotho lwesamente ezisezantsi zokulahla izinto zokulahla. Amanyathelo aphambili obugcisa: ngokuqulunqa ii-oven curves ezifanelekileyo kunye nokwazisa i-anti-explosion agents ezigqwesileyo, njl., oku kunokwenza i-refractory castables Amanzi apheliswe kakuhle ngaphandle kokubangela ezinye iziphumo.
Itekhnoloji yomgubo we-Ultrafine yeyona nto iphambili yobuchwepheshe kuthotho lwesamente esezantsi yokulahla izinto ezilahlwayo (okwangoku uninzi lwemigubo ye-ultrafine esetyenziswa kwiiseramics kunye nemathiriyeli echasayo eneneni iphakathi kwe-0.1 kunye ne-10m, kwaye isebenza ikakhulu njenge-accelerators kunye ne-structural densifiers. amasuntswana isamente kakhulu yahlakazeka ngaphandle flocculation, lo gama yokugqibela yenza micropores kumzimba ethululwayo izaliswe ngokupheleleyo kwaye iphucula amandla.
Okwangoku iintlobo ezisetyenziswa ngokuqhelekileyo ze-ultrafine powders ziquka i-SiO2, i-α-Al2O3, i-Cr2O3, njl. Indawo ethile yendawo ye-SiO2 micropowder i malunga ne-20m2 / g, kwaye ubungakanani bayo be-particle bu malunga ne-1/100 yesayizi ye-samente, ngoko ilungile. iipropati zokugcwalisa. Ukongeza, i-SiO2, i-Al2O3, i-Cr2O3 micropowder, njl. Xa i-dispersant ikhona, umaleko ombane ophindwe kabini wenziwa kumphezulu wamasuntswana ukuvelisa i-electrostatic repulsion, eyoyisa i-van der Waals force phakathi kwamasuntswana kunye nokunciphisa ujongano lwamandla. Ikhusela i-adsorption kunye ne-flocculation phakathi kwamasuntswana; kwangaxeshanye, i-dispersant i-adsorbed ejikeleze amasuntswana ukwenza umaleko we-solvent, okwandisa ukugqithiswa kwe-castable. Le ngenye yeendlela ze-ultrafine powder, oko kukuthi, ukongeza i-ultrafine powder kunye ne-dispersants efanelekileyo kunokunciphisa ukusetyenziswa kwamanzi okuchithwa kwe-refractory kunye nokuphucula umbane.
Ukumiselwa kunye nokuqina kwe-samente ephantsi ye-refractory castables yiphumo lesenzo esidibeneyo sokubambisana kwe-hydration kunye ne-cohesion bonding. I-hydration kunye nokuqina kwesamente ye-calcium aluminate cement ubukhulu becala kukuhanjiswa kwezigaba ze-hydraulic CA kunye ne-CA2 kunye nenkqubo yokukhula kwekristale ye-hydrates yabo, oko kukuthi, basabela ngamanzi ukwenza i-hexagonal flake okanye i-CAH10, i-C2AH8 kunye neemveliso ze-Hydration ezinjalo. njengeekristale ze-cubic C3AH6 kunye neegels ze-Al2O3аq emva koko zenze i-condensation-crystallization network structure ngexesha lokunyanga kunye neenkqubo zokufudumeza. I-agglomeration kunye ne-bonding kungenxa ye-SiO2 ultrafine powder esebenzayo eyenza amasuntswana e-colloidal xa idibana namanzi, kwaye idibana nee-ion ezihlulwe ngokucothayo kwi-additive additive (okt i-electrolyte substance). Ngenxa yokuba iintlawuliso ezingaphezulu kwezi zimbini zichasene, oko kukuthi, umphezulu we-colloid une-adsorbed counter ion, ebangela ukuba i-£ 2 enokwenzeka iyancipha kwaye i-condensation yenzeke xa i-adsorption ifikelela kwi-"isoelectric point". Ngamanye amazwi, xa i-electrostatic repulsion kumphezulu wamasuntswana e-colloidal ingaphantsi komtsalane wayo, ukudibanisa okudibeneyo kwenzeka ngoncedo lwamandla e-van der Waals. Emva kokuba i-refractory castable exutywe kunye ne-silica powder igxininiswe, amaqela e-Si-OH akhiwe phezu komhlaba we-SiO2 omisiwe kwaye aphelelwe ngamanzi kwibhuloho, enze i-siloxane (i-Si-O-Si) isakhiwo sothungelwano, ngaloo ndlela lukhuni. Kwisakhiwo senethiwekhi ye-siloxane, izibophelelo phakathi kwe-silicon kunye ne-oksijini azinciphi njengoko izinga lokushisa linyuka, ngoko ke amandla ayaqhubeka nokukhula. Ngexesha elifanayo, kwiqondo lokushisa eliphezulu, isakhiwo senethiwekhi ye-SiO2 siya kusabela kunye ne-Al2O3 ehlanganiswe kuyo ukuze yenze i-mullite, enokuphucula amandla kwiqondo lokushisa eliphakathi kunye neliphezulu.
Ixesha lokuposa: Feb-28-2024
