热处理温度对ZrO2纤维复合ZrO2-C材料性能的影响

浸入式水口是钢铁连铸工序中关键的功能耐火材料,其中以渣线部位的工作环境最为恶劣。目前,最适合的渣线材料是ZrO₂-C材料。为了提高浸入式水口的性能,本文以氧化锆与鳞片石墨为主要原料,添加增强材料氧化锆纤维及金属硅粉等,以酚醛树脂为结合剂制备ZrO₂-C复合材料。比较了1 000 ℃、1 200 ℃和1 500 ℃三种热处理温度对ZrO₂-C材料的性能及显微结构的影响,结果表明,在热处理温度高于1 200 ℃时,ZrO₂-C材料中的硅粉与石墨发生反应生成碳化硅,大量晶须状碳化硅与ZrO₂纤维交错在一起形成网络结构,提高了材料的力学性能和抗热震性。

Effect of Heat Treatment Temperature on Properties of ZrO2 Fiber Composite ZrO2-C Material

Submersed entry nozzle is critical functional refractories in continuous casting and the slag line parts has the worst working environment. At present, the most suitable slag line material is ZrO₂-C material. In order to improve the performance of submersed entry nozzle, ZrO₂-C material was prepared by using zirconia and flake graphite as the main raw materials, zirconia fiber and metal silica powder as reinforcement materials, and phenolic resin as binder. The effects of three heat treatment temperatures, 1 000 ℃, 1 200 ℃ and 1 500 ℃, were compared on the properties and microstructure of ZrO₂-C material. The results show that when the heat treatment temperature is higher than 1 200 ℃, the silicon powder reacts with carbon to form silicon carbide, and a large number of whisker silicon carbide interleaves with ZrO₂ fiber to form a network structure, which improves the mechanical properties and thermal shock resistance of the material.