摘要
为提高铝碳材料的性能,在碳结合的基础上增加陶瓷结合相,将添加铝粉的铝碳试样在不同气氛 (Ar、埋炭和N2 )中经 1300℃热处理 5h,测定试样热处理前后质量变化率、抗折强度、体积密度、显气孔率和抗水化性,并用扫描电镜和XRD分析试样的显微结构和物相组成。研究表明: 埋炭保护热处理后材料中有大量亚微米级柱状和类柱状物的晶须;Ar保护热处理后材料中有带状、锥状的氧化铝和少量晶须生成;N2保护热处理后材料中有较多粒状AlN产生;热处理气氛不同,材料显微结构明显不同,但不能避免Al4C3的生成;埋炭和N2保护热处理后,材料强度提高,显气孔率降低;N2保护热处理最有助于提高材料的抗水化性。
In order to improve the property of alumina graphite material by increasing ceramic bond,the alumina graphite specimens added with metal aluminum were prepared and heat-treated at 1300 ℃ for 300 minutes in three different atmospheres including argon,CO+N_2 and nitrogen,respectively.The mass change,cold MOR, bulk density,apparent porosity and hydration resistance of the specimens before and after heat treatment were determined,the phase compositions and microstructures were studied by XRD analysis and SEM.The results reveal that different atmospheres would result in different microstructures but could not prevent the formation of Al_4C_3.After heat-treatment in CO+N_2 atmosphere,sub micrometer whiskers shaped like the column exist in specimens A-A.But lots of floccules,band shaped and hexagonal coniform like whiskers are presented in specimens A-A heat-treated in Ar atmosphere and granular AlN in A-A specimens heat-treated in N_2 atmosphere.For specimens heat-treated in CO+N_2 or nitrogen atmosphere,their MORs increase and apparent porosities decrease.Heat-treatment in nitrogen atmosphere was favorable to improve hydration resistance of alumina graphite specimens added with Al.
出处
《耐火材料》
EI
CAS
北大核心
2005年第1期26-30,35,共6页
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