【摘要】 以粒度3～5mm,1～3mm,≤1mm,≤0.088mm的高铝矾土为主要原料,以粒度≤0.1mm的硼酸(H3BO3>99.6%)、粒度≤0.05mm的粘土、粒度≤0.1mm的钾长石和粒度≤0.1μm的硅灰(SiO2>90%)为复合烧结剂,按m(骨料)∶m(细粉)=65∶35的配比配料。将混合料在陶瓷模具中手工捣打成型,将成型好的试样分别在600℃、700℃、800℃、900℃和1000℃下均保温2h后脱模。测量热处理后各试样的耐压强度和显气孔率;采用XRD分析了试样的物相组成。结果表明:复合烧结剂中钾长石和硼酸在中温、低温下具有良好的烧结作用,在700～800℃热处理后,试样耐压强度和显气孔率明显增加。硼酸含量为2%的试样,在800～1000℃热处理后,显气孔率增幅较大。添加硅灰可以降低钾长石烧结温度;而复合烧结剂中的粘土在中温、低温下不利于干式料的烧结,低于800℃热处理后的试样,耐压强度和显气孔率没有随粘土含量增加而变化;900～1000℃热处理后的试样,耐压强度随粘土含量的增加而降低,显气孔率增加不大。更多还原

【Abstract】 The mixture was prepared using bauxite with particle size 3~5 mm,1~3 mm,<1 mm and <0.088 mm as starting materials,<1 mm boric acid(H3BO3>99.6%),<0.05 mm clay,<0.1 mm K-feldspar and <0.1 μm microsilica (SiO2>90%)as composite sintering agents,with 65∶35 of the ratio of aggregate and powder.Specimen was made by manually ramming the mixture in ceramic mould,firing at 600 ℃,700 ℃,800 ℃,900 ℃ and 1 000 ℃ for 2 h respectively,then demoulding.Crushing strength and apparent porosity were measured,and phase composition was analyzed by XRD.The result showed:K-feldspar and boric acid had good sintering effect at low and middle temperature.Crushing strength and apparent porosity of specimen fired at 700~800 ℃ obviously increased.Apparent porosity of specimen with 2% boric acid fired at 800~1 000 ℃ markedly increased.Microsilica can decrease the sintering temperature of K-feldspar.Clay had bad influence on the sintering of dry ramming mix at low and middle temperature.Crushing strength and apparent porosity of specimen fired at lower than 800 ℃ didn’t change with the increase of clay content.Crushing strength of the specimen fired at 900~1 000 ℃ decreased with the increase of clay content,but apparent porosity increased slightly.更多还原