不同造孔剂对SiCp/Al复合材料中多孔预制体性能的影响

Influence of Different Pore-forming Agents on Properties of Porous Preform of SiCp/Al Composites

采用无压浸渗法制备SiCp/Al复合材料,主要分析了淀粉、硬脂酸和石墨三种不同造孔剂对多孔预制体组织结构和性能的影响。结果表明:三种不同造孔剂对预制件的孔隙分布影响很小;以石墨为造孔剂的预制件有一部分SiC颗粒在高温下氧化生成SiO2,形成的烧结颈,氧化生成的SiO2膜层对SiC颗粒起到一定的连接作用,使得预制件的强度增大。

SiCp/AI composites were fabricated with pressureless infiltration technique. The effects of three pore-forming agents of starch, stearic acid and graphite on properties of porous preform of SiCp/A1 composites were investigated. The results show that the three agents affect little to the pore distribution of the performs; A portion of SiC particles in performs with graphite as pore-forming agents oxidize to SiO2 at high temperature. The SiO2film produced by oxidation played a junctionj role to the SiC particles ,enhancing the strength of performs.