以3~2mm、2~1mm、1~0.5mm、〈0.5mm四个粒级的电熔镁砂颗粒,〈0.074mm的电熔镁砂粉和〈0.043mm的电熔共晶镁锆粉为原料,采用不同的电熔镁砂颗粒级配进行配料,以聚乙烯醇-木质素磺酸钙混合溶液为结合剂.以100MPa的压力成型为53mm×10mm×10mm的试样,分别在1550℃、1600℃、1650℃、1700℃、1750℃和1800℃保温2h煅烧。检测了烧成后试样的显气孔率、体积密度和常温抗折强度,并对烧后试样进行了抗水泥熟料侵蚀试验,同时对烧后试样和抗水泥熟料侵蚀后试样进行了SEM分析。结果表明:试样在1700℃保温2h煅烧后的烧结程度最高;粒度组成对试样的烧结程度影响较小;由于形成CaZrO3的体积膨胀效应以及冷却过程中C2S多晶转变的体积膨胀效应,抗水泥熟料侵蚀试验后试样的显气孔率增加,强度降低。
Four gradings of fused magnesite grains with respective range of 3 -2 mm,2 - 1 mm,1 -0.5 mm and 〈0.5 mm,fused magnesite powders with size 〈0.074 mm and fused magnesia -zirconia with size 〈0. 043 mm are used as starting materials for preparing rebonded MgO -ZrO2 multiphase material. The mixed powders are bonded by polyvinyl alcohol and calcium lignosulfonate solution and then pressed with the size of 53 mm × 10 mm× 10 mm under 100 MPa. Finally the specimens are fired at 1550 ℃, 1600 ℃, 1650 ℃, 1700 ℃,1750 ℃ and 1800 ℃ for 2 h respectively. The apparent porosity, bulk density and cold modulus of rupture of the specimens are determined. The erosion resistance to cement clinker of specimens is also tested and the fired and eroded specimens are analyzed by SEM. The results show that: (1)The specimen fired at 1700 ℃ is of the highest density;(2)The influence of the grain sizes on sintering density can be ignored; (3) Owing to the volumetric expansion effect of CaZrO3 and C2S polycrystalline transformation,the apparent porosity of the eroded specimens increased and the strength decreased.