用废弃含碳耐火材料合成方镁石-镁铝尖晶石复相材料

Synthesis of Periclase-magnesium Aluminum Spinel Recombination Materials by Used Carbon-bearing Refractory

以废弃镁碳砖与废弃滑板为原料,分别按照n(MgO)/n(Al2O3)=1,2,3,4比例进行制样,通过1300℃、1400℃、1500℃保温2 h对试样进行煅烧。用X射线衍射仪、扫描电镜及X'Pert plus软件对热处理后试样的组成和结构进行表征。结果发现:以废弃镁碳砖与废弃滑板可以合成出方镁石-尖晶石复相材料,随着废弃镁碳砖引入量增加;试样体积密度降低,显气孔率增加,结构组成中方镁石逐渐增加。煅烧温度的增加促进方镁石与刚玉相形成镁铝尖晶石相。当n(MgO)/n(Al2O3)=3,煅烧温度1500℃时,经煅烧后形成方镁石-尖晶石复相结构中结晶相方镁石含量达到33%,镁铝尖晶石59%,方镁石-尖晶石相间由结晶度较差的玻璃相粘结。

Periclase-magnesium aluminum spinel recombination material was prepared by used slide plate and used M-C brick according to n（MgO）/n（Al2O3）=1,2,3,4 sintered at 1300 ℃,1400 ℃,1500 ℃ respectively.The main crystalline phase and microstructure of sintered specimens were examined by X ray diffraction,scanning electron microscopy and X＇ Pert plus software.The result showed that periclase-magnesium aluminum spinel recombination material was synthesized by used slide plate and used M-C brick.With the increase of used M-C brick addition,the bulk density of sample decreased,while apparent porosity increased,and periclase content decreased in the structure.Increasing of sintering temperature accelerated the production of magnesium aluminum spinel which was formed by periclase and corundum in crystalline phase.Crystalline phase periclase 33%,crystalline phase magnesium aluminum spinel 59% in the periclase-magnesium aluminum spinel recombination structure by calcinations at 1500 ℃ and n（MgO）/n（Al2O3）=3.Crystalline phase were bonded by glass phase in phase boundary of periclase and magnesium aluminum spinel.