摘要
以电熔镁砂、鳞片石墨以及Al-Mg合金粉、金属Si粉为原料,以Ni(NO_3)_2·6H_2O为催化剂,以酚醛树脂为结合剂,在经配料、混合、成型后,分别在1200、1400℃埋炭条件下进行热处理制备了MgO-C耐火材料。研究了不同催化剂添加量对Mg O-C耐火材料物相组成、显微结构特征和试样抗热震及力学性能的影响。结果表明:经1200℃热处理后,试样中Al-Mg合金被氧化,进一步反应生成镁铝尖晶石;经1400℃热处理后,Si单质消失,试样中有Si C生成,镁铝尖晶石生成量增加,并且有Al N相生成;当催化剂加入量分别为0.4%、0.6%时,试样基质中可原位生成镁铝尖晶石晶须,Si C及Al N等陶瓷相,试样的抗热震性能和断裂韧性都得到提高。
Mg O-C refractory samples were prepared using fused magnesia, flake graphite, Al-Mg alloy and Si powders as raw materials, Ni(NO_3)_2·6H_2O as catalyst and phenolic resin as binder. After mixing and pressing, the specimens were coked in reducing atmosphere at 1200 ℃ and 1400 ℃ for 3 h. The characteristics of phase composition, microstructure, thermal shock resistance and mechanical strength of the samples with different catalyst contents were studied. The results show that after 1200 ℃ heating treatment, the Al-Mg alloy has been oxidized and turned into Mg Al_2O_4. After 1400 ℃ heating treatment, there appear Al N and Si C ceramic phases while metallic Si disappears. At the same time, the amount of Mg Al_2O_4 formation increases. When the contents of Ni(NO_3)_2·6H_2O are more than 0.4%, the thermal shock resistance and fracture toughness of specimens are improved significantly, which should be contributed to the formation of Si C, Al N and Mg Al2O4 whiskers.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2015年第S1期438-441,共4页
Rare Metal Materials and Engineering
基金
国家自然科学基金(51174152)
国家"973"计划(2012CB722702)
湖北省自然科学基金重点项目(2014CFA091)
