Fe 粉对 MgO－C 材料显微结构和性能的影响

摘要

MgO-C refractories specimens were prepared using fused magnesia,carbon black,graphite,Si powders as starting materials,hot-setting phenolic resin as binder and Fe powder as catalyst.After carbon embedding treatment at 1 200 ℃ and 1 400 ℃,respectively,the influence of Fe powder on the phase com-position,microstructure and thermal shock resistance was studied.The results show that Fe powders have little influence on phase composition;some new phases such as SiO2 and Mg2 SiO4 form after 1 200 ℃ treat-ment.After 1 400 ℃ treatment,SiO2 reacts forming a new phase SiC.The morphology of Mg2 SiO4 is colum-nar in the specimens without Fe powder,while the morphology of Mg2 SiO4 is whiskers in the specimens with Fe powder.Adding Fe powder increases the residual strength ratio of CMOR after one thermal shock from 1 100 ℃ to water quenching for the heat-treated specimens,and improves the strength and thermal shock resistance.%以电熔镁砂、炭黑、石墨以及 Si 粉为原料，热固性酚醛树脂为结合剂，Fe 粉为催化剂，分别经1200和1400℃埋炭热处理后制备了 MgO－C 试样，研究了不同温度下催化剂 Fe 粉对试样的物相组成、显微结构以及抗热震性能的影响。结果表明：Fe 粉的加入对试样的物相组成基本无影响，经1200℃热处理后的试样中生成了新物相 SiO2和 Mg2 SiO4；当温度升高至1400℃时，试样中的 SiO2参与反应生成了新相 SiC。不含 Fe 粉试样中生成的Mg2 SiO4呈柱状，而含 Fe 粉试样中的 Mg2 SiO4呈晶须状。经不同温度热处理后，含 Fe 粉试样经热震1次后（1100℃，水冷）的残余抗折强度均高于不含催化剂的，Fe 粉的加入使试样具有更好的强度和更加优异的抗热震性能。