金属Zn粉对Al_2O_3-C耐火材料抗氧化性能的影响

Effect of metal Zn powder on oxidation resistance of Al_2O_3-C refractories

以板状刚玉、鳞片石墨、Zn粉、Al粉和Si粉为主要原料,以酚醛树脂为结合剂,固定配料中板状刚玉、鳞片石墨、Al粉和Si粉的比例,分别外加0、0.5%、1%、2%和3%的Zn粉制成5组Al2O3-C试样,在120～220℃进行24h干燥处理,然后在1400℃空气气氛中加热3h,冷却后测量试样的质量变化率、脱碳层厚度、显气孔率和体积密度,同时进行显微结构观察和微区成分分析。结果表明:加入2%Zn粉的Al2O3-C试样的脱碳层厚度最小,显气孔率最低,体积密度最大,因此推断其抗氧化性能最佳。

Al2O3 -C specimens were prepared by using tabular corundum, flaky graphite, Al, Si and Zn powder as starting materials and phenolic resin as binder. With the mass ratios of tabulat corundum,flaky graphite,AI and Si constant,various contents of Zn（0,0. 5%, 1% ,2% ,3% ） were added respectively. The specimens were heat treated at 120 -220 ℃ for 24 h,and then fired at 1400 ℃ for 3 h in air atmosphere. The mass change rate,thickness of clecarburization layer, apparent porosity and bulk density and microstructure of the products were determined and observed by means of SEM and EDX. The results show that the specimen with 2% Zn was characterized by minimum thickness of decarburization layer and apparent porosity and maximum bulk density. Consequently,the specimen with 2% metal Zn is supposed to perform the best oxidation resistance.