Ibyuma bito birwanya sima bigereranywa n'ibisanzwe birwanya sima birwanya sima. Ingano yongerwaho sima y'ibicuruzwa birwanya sima birwanya sima bikunze kuba 12-20%, naho amazi yongerwaho muri rusange akaba 9-13%. Bitewe n'amazi menshi yongewemo, igice cy'icyuma gifite imyenge myinshi, ntabwo ari kinini, kandi gifite imbaraga nke; bitewe n'ingano nini ya sima yongewemo, nubwo imbaraga nyinshi zisanzwe n'iziciriritse zishobora kuboneka, imbaraga ziragabanuka bitewe n'impinduka za calcium aluminate ku bushyuhe buringaniye. Birumvikana ko CaO yinjijwe ikorana na SiO2 na Al2O3 mu cyuma gishonga kugira ngo ikore ibintu bimwe na bimwe bishobora gushonga buhoro buhoro, bigatuma imiterere y'ibikoresho bishyuha cyane igabanuka.
Iyo hakoreshejwe ikoranabuhanga rya ultrafine powder, imvange zikora neza cyane hamwe n’uburyo bwa siyansi bwo gukuraho uduce duto, ingano ya sima mu icupa igabanuka ikagera munsi ya 8%, amazi akagabanuka akagera kuri ≤7%, kandi icupa rito rishobora gutegurwa rigashyirwa muri CaO ni ≤2.5%, kandi ibipimo by’imikorere yaryo muri rusange birenga iby’icupa rito rishobora gukurwaho muri sima. Ubu bwoko bwa icupa rito rishobora gukurwaho bufite thixotropy nziza, ni ukuvuga ko ibikoresho bivanze bifite imiterere runaka kandi bigatangira gutemba n’imbaraga nke zo hanze. Iyo imbaraga zo hanze zikuweho, zigumana imiterere yabonetse. Kubwibyo, nanone yitwa thixotropic idashobora gukurwaho. Icupa rito rishobora gukurwaho ryitwa thixotropic idashobora gukurwaho. Riri muri iki cyiciro. Igisobanuro nyacyo cy’icupa rito ridashobora gukurwaho ry’icupa ntikirasobanurwa kugeza ubu. Ishyirahamwe ry’Abanyamerika rishinzwe ibizamini n’ibikoresho (ASTM) rigena kandi rigashyira mu byiciro icupa ridashobora gukurwaho ry’icupa rishingiye ku ngano ya CaO.
Ubucucike bwinshi kandi bukomeye ni byo biranga ibikoresho bito bito bitagira sima nini. Ibi ni byiza mu kunoza ubuzima n'imikorere y'umusaruro, ariko binateza ibibazo mu guteka mbere yo kubikoresha, ni ukuvuga ko gusuka bishobora kubaho byoroshye niba utitonze mu gihe cyo guteka. Indwara yo guturika kw'umubiri ishobora gusaba kongera gusukwa byibuze, cyangwa ishobora gushyira mu kaga umutekano w'abakozi bayikikije mu bihe bikomeye. Kubwibyo, ibihugu bitandukanye byanakoze ubushakashatsi butandukanye ku guteka ibikoresho bito bitagira sima nini. Ingamba z'ingenzi za tekiniki ni: mu gukora imigozi y'ifuru ikwiye no gushyiraho imiti myiza irwanya guturika, nibindi, ibi bishobora gutuma ibikoresho bito bitagira sima nini bikurwaho neza nta ngaruka mbi bitera.
Ikoranabuhanga rya Ultrafine powder ni ryo koranabuhanga ry'ingenzi ku bikoresho bigabanya sima (ubu ifu nyinshi zikoreshwa mu bikoresho bigabanya sima mu buryo bukabije ziri hagati ya metero 0.1 na 10, kandi ahanini zikora nk'ibinyabutabire byo gukwirakwiza no gukurura imiterere y'ibintu. Iya mbere ituma ibice bya sima bitatana cyane nta gushonga, mu gihe iya nyuma ituma uduce twa sima mu gice cyo gusukwa twuzura neza kandi tukongera imbaraga.
Ubwoko bukunze gukoreshwa bw'ifu ikoze mu buryo bwa ultrafine burimo SiO2, α-Al2O3, Cr2O3, n'ibindi. Ubuso bwihariye bwa SiO2 micropowder ni hafi 20m2/g, kandi ingano yayo ni hafi 1/100 cy'ingano y'uduce twa sima, bityo ikaba ifite ubushobozi bwo kuzuza neza. Byongeye kandi, SiO2, Al2O3, Cr2O3 micropowder, nibindi bishobora no gukora uduce twa colloidal mu mazi. Iyo hari icyuma gikwirakwiza amazi, urwego rw'amashanyarazi rufatanye rukorwa ku buso bw'uduce kugira ngo rutange imbaraga za electrostatic, zitsinda imbaraga za van der Waals hagati y'uduce kandi zigabanye ingufu zo guhuza. Birinda ko amazi asohoka no guhindagurika hagati y'uduce; muri icyo gihe, icyuma gikwirakwiza amazi gishyirwa ku duce kugira ngo kibe urwego rwa solvent, ibyo bikaba byongera ubwinshi bw'amazi akoreshwa mu gusuka amazi. Iyi nayo ni imwe mu mikorere y'ifu ikoze mu buryo bwa ultrafine, ni ukuvuga ko kongeramo ifu ikoze mu buryo bwa ultrafine no gusuka amazi bikwiye bishobora kugabanya ikoreshwa ry'amazi y'uduce dukoresha amazi kandi bikongera ubwinshi bw'amazi.
Imiterere n'ubukomere bw'ibikoresho bito bitagira sima ihagije ni ingaruka z'ibikorwa byo guhuza amazi n'ubufatanye. Ubushyuhe n'ubukomere bwa sima ya calcium aluminate ahanini ni ubushyuhe bwa CA na CA2 mu byiciro bya hydraulic ndetse n'uburyo crystal growth ya hydrates zabyo, ni ukuvuga ko bikora hamwe n'amazi kugira ngo bikore shexagonal flake cyangwa CAH10, C2AH8 na Hydration products nk'uduseke twa cubic C3AH6 na Al2O3аq gels hanyuma bigakora imiterere y'urusobe rw'amazi n'ubushyuhe mu gihe cyo gushyushya no gushyushya. Guterana no guhuza biterwa n'ifu ya SiO2 ultrafine ikora uduce twa colloidal iyo ihuye n'amazi, kandi igahura na iyoni itandukana buhoro buhoro n'inyongera (ni ukuvuga electrolyte substance). Kubera ko imbaraga z'ubuso bw'ibi byombi ziba zitandukanye, ni ukuvuga ko ubuso bwa colloide bufite iyoni zirimo amayoni, bigatuma £2 ubushobozi bugabanuka kandi amazi akabaho iyo amayoni ageze ku "isoelectric point". Mu yandi magambo, iyo imbaraga zikoreshwa mu gukurura amashanyarazi ku buso bw'uduce twa colloidal zitari zihagije, imikoranire ihuza ibaho hifashishijwe imbaraga za van der Waals. Nyuma y'uko agakoresho gashobora gucika kavanze n'ifu ya silica gashyizwe hamwe, amatsinda ya Si-OH agizwe ku buso bwa SiO2 yumishwa kandi agakurwa amazi kugira ngo ahuzwe, hagakorwa imiterere y'urusobe rwa siloxane (Si-O-Si), bityo bigakomera. Mu miterere y'urusobe rwa siloxane, imikoranire hagati ya silicone na ogisijeni ntigabanuka uko ubushyuhe bwiyongera, bityo imbaraga nazo zigakomeza kwiyongera. Muri icyo gihe, ku bushyuhe bwinshi, imiterere y'urusobe rwa SiO2 izakorana na Al2O3 ipfunyitsemo kugira ngo ikore mullite, ishobora kongera imbaraga ku bushyuhe buri hagati n'ubushyuhe buri hejuru.
Igihe cyo kohereza: Gashyantare-28-2024
