Low Temperature (<900 ¡ã C) Sintered Ceramic Formulations And Production Technology Research

This paPer systematicall}' summarized the current status of the studyof low temperature ceramics, main production technologies and application.A low temperature ceramic u'ith the sifltering temPerature in the range of850'C~870"C was produced, \vhich selected the raw materials includingwaster glass, sintering aluminum oxide, clay etc. The main crystal phase ofthe materia1s was corundum, Which was measured by XRD; Themicrostructure was measured by SEM. The results showed that themicrostfuctures were consistent between the low temperature ceramics andthe common domestic potter}' and porcelain, Which were composed withglass phase, crystal phase and few gas phases. As we all knoW the skeletonof the body was constituted u-ith crystals, and the glass phase was fil1ed inthe skeleton. The differences between the common domestic pottery andskeleton porcelain and the lou' temPerature ceramics showed that the mainmulti-crystal in the fOrmer tt-as extracted from glass melt by physicalchemical reaction in high temperature. However, the crystal involvingcorundum and cristobalite etc all came from the material itself in the later.The density of low temperatUre ware resulted from adhesion flowsproduced from the body materials, which caused by the surface tension inliquid phase.The sintering mechanism of quasi-Nonreactive was researched. Theeffect factors were inquired too. The sintering factors affectedquasi-Nonreactive including the softening temperature of waster glass, thesize of the particles and the adding contents of waster glass. The.'softening temperature of waster glass was loweF, the particles size weresmaller and the waster glass content were higher, the sintering temperature'was lower and the sintering 1'elocity was quickef, Which were consistentwith the relative density change velocity formula: P=H(l --e)' whichdt 2mwere deduced from theory in the course of sintering. The research showedthat when glass phase content amounted to 40--60%, the average size ofparticles was about 10Um in the raw materials during quasi-Nonreactive,the ceramics could be sintered aPporaching-softening temperature with 1h.The barren materials in the body material amounted to 60% and lowplastic and moulding. The plastic mechanism of the plasticizer wascompositively studied for deciding on the plan utilized by severalplasticizers. The study showed that When the adding contents of the aquaticmaterials JA, Polyscaccharide HS, sodium humate were 0.l5%, 0.2%,0.2%(dry raw material) respectively, the plastic index of the raw materialwas added from 0.l8kg.cm to3.42kg.cm, which are accorded with thedemands of moulding.The stabi1ity of ceramic slurry with glass powders as major rawmaterials was researched. The results showed that when PH=7and theconteflt of polyacrylic acid as diluent amounted to 0.4%, the stability andrelease modeling property were all excellent.