关键词: 硅粉加入量;碳纤维复合铝碳耐火材料;显微结构;强度

Abstract: Carbon fiber reinforced alumina-carbon refractories containing different silicon powder content (0-20%) were prepared by using fused white corundum as aggregate, and graphite, carbon fiber, corundum powder as matrix, and silicon powder as additive, fixed total mass percentage (29%) of white corundum powder and silicon powder.The phase compositions, microstructures and strengths of samples heated at different temperature were analyzed by the XRD, SEM and EDS.The results demonstrate that:(1) When the heating temperature is 220 ℃, with an increase of silicon powder content from 0 to 8%, the compressive and flexural strengths change little;whereas, with an increase of silicon powder content from 8% to 20%, the compression and flexural strengths are reduced.(2) When the heating temperature is 1400 ℃, with an increase of silicon powder content from 0 to 8%, the compressive and flexural strengths are significantly improved;with a further increase of silicon powder content, some cracks appeare on the surface of the samples, and then the strength decrease sharply.(3) The most appropriate mode is a sample containing 8% silicon powder, which has optimal performance after heated at 220 ℃ and 1400 ℃.

Key words: silicon powder content;carbon fiber reinforced Al2O3-C refractory;microstructure;strength