简介:硬质聚氯乙烯结皮低发泡钢塑共挤型材(简称JFG型材)自1997年问世以来,先后在北京、河北、山东、黑龙江、新疆、云南等地投产。它采用钢塑复合技术及结皮低发泡生产工艺,将U—PVC发泡材料巧妙地复合在异型钢衬上,形成表层为U—PVC结皮层,中间为U—PVC发泡层,里面为钢衬的多层结构,是一种“钢塑
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简介:TherearemanyprocessestoproduceCr2O3fromchrome-ores,DifferentparticlesizerangesofCr2O3powder,finepinmentgradegreenCr2O3andcoarsemetallurgygradeblackCr2O3,aremadebydifferentprocessesinChina,GreenCr2O3assuperfineandadditionandmetallurgygradeblackCr2O3usedtosynthesizeCr2O3graincanbeappliedtorefractories.ItisverydifficultforhighpurityCr2O3tosintertodensificationandTiO2additioniscontributedtodensificationofCr2O3sinteredathightemperature,Cr2O3grainswithrelativedensityof91%-95%aregainedbysinteringCr2O3withTiO2additionandelectrofusingCr2O3rawmaterials.