造孔剂含量对多孔SiC预制件孔隙率的影响及孔隙率测定方法探究  

Effect of Pore-forming Agents Content on Porosity and Experimental Study on Porosity Measurement of Porous SiC Preform

作　　者：刘玫潭[1,2] 蔡旭升[1,2] 何丽娇[1,2] 李国强[1,2] 

机构地区：[1]华南理工大学发光材料与器件国家重点实验室,广州510640 [2]华南理工大学材料科学与工程学院,广州510640

出　　处：《材料导报》2013年第14期108-112,共5页Materials Reports

基　　金：国家安全重大基础研究(国防973);国家自然科学基金(51002052);广东省战略新兴产业专项资金(2011A081301010)

摘　　要：采用模压成型法制备了SiC预制件,分别采用阿基米德法、质量体积法和压汞仪法测试了其孔隙率,并对测试结果进行比较分析。结果表明,阿基米德法测试结果偏小,这是因为此方法测量的是孔径较大的气孔的显气孔率;质量体积法与压汞仪法测试结果较为接近。比较AlSiC复合材料中Al合金体积分数和3种方法的测试结果表明,质量体积法测试结果与Al合金体积分数最接近,是一种简单可靠的孔隙率测试方法。进一步探究了预制件孔隙率与造孔剂含量之间的关系。结果表明,当造孔剂含量较少时,孔隙率增加不明显,当造孔剂含量高于5%时,随着造孔剂含量的增加,孔隙率大体上呈线性增加趋势。当造孔剂含量为14%时,孔隙率近40%,完全满足后续渗Al需要。The SiC preform was prepared by compression molding. The porosity of porous SiC preform was de- termined by Archimedes method, mass-volume method and mercury intrusion method, the measured results were com- pared. The results showed that the porosity measured by Archimedes method was small because the open porosity was large, the test results of mass-volume method and mercury intrusion method were near, then A1 alloy volu-me fraction in A1SiC composite and porosities measured by the above three methods were also compared. The results proved that the porosity measured by mass-volume method has an excellent agreement with A1 alloy volume fraction in A1SiC com- posite. Therefore the mass volume method is a simple and practical method of porosity measuring. Then the effects of the pore-forming agents content on the porosity of SiC porous preform were investigated. The results showed that the porosity rose unohviously with the content of pore-forming agents when content of pore-forming agents was less than 5 % and that the porosity rose linearly in general when content of pore-forming agents was more than 5%. And the porosity tended to 40% when the pore-making agents content was 14%, which can fully meets subsequent A1 infiltra- tion requirements.

关 键 词：SiC预制件 孔隙率 压汞仪法 质量体积法 阿基米德法 造孔剂 

分 类 号：TG146[一般工业技术—材料科学与工程]