合成ZrO_2-SiC和工业SiC对Al_2O_3-C质耐火材料性能影响的对比

Influences of ZrO_2-SiC composite powder and commercial SiC on properties of Al_2O_3-C refractories

为了改善Al2O3-C质耐火材料的抗氧化性和抗热震性,向浇注料中分别添加0、2%、4%、6%的SiC或ZrO2-SiC复合粉,以酚醛树脂为结合剂,在200MPa下制备了2组试样,经250℃充分干燥后,于1400℃下埋炭处理2h,分别检测2组试样的抗氧化性和抗热震性,并采用XRD分析氧化后试样的相组成。结果发现,添加剂中SiC的氧化能有效保护试样中的碳,从而能减少试样的质量损失率和氧化面积,提高其抗氧化性能。由于ZrO2的微裂纹增韧及SiC的颗粒增韧作用,使试样的抗热震性能提高。在试验条件下,添加6%ZrO2-SiC复合粉或工业SiC粉时,试样的抗氧化性和抗热震性最佳。

In order to improve oxidation resistance and thermal shock resistance of Al2O3 -C refractories,two groups of specimens were prepared with phenolic resin as binder,adding 0,2% ,4% and 6% SiC or ZrO2 -SiC composite powder respectively to Al2O3 -C refractories, pressing at 200 MPa,drying fully at 250 ℃,then carbon embedded firing at 1 400 ℃ for 2 h. Oxidation resistance and thermal shock resistance were researched, phase composition was analyzed by XRD. The results show that：The oxidation of SiC in additives can protect carbon in specimens effectively and thus decrease the mass loss ratio and oxidation area, and improve the oxidation resistance of the specimen. Thermal shock resistance is improved owing to the microcrack toughening of ZrO2 and grain toughening of SiC. In this experiment,the specimens with 6% ZrO2 -SiC composite powder or SiC powder have the best oxidation and thermal shock resistance.