高强度SiC陶瓷泡沫的变形特性

Deformation Performance of High Strength Silicon Carbide Ceramic Foams

关键词:  SiC陶瓷泡沫,表观密度,强度,变形行为,线弹性行为

Key words:  silicon cabide(SiC) ceramic foam,apparent density,strength,deformation behavior,linear-elastic behavior

摘要:

制备了具有三维连通网状开放结构的碳化硅(SiC)陶瓷泡沫,并测试了其机械性能.SiC陶瓷泡沫表观密度可控制在0.4~1.3 g/cm3,相应的抗压强度为8~50 MPa、抗折强度为3~30 MPa.通过压缩测试得到了SiC陶瓷泡沫应力-应变曲线,发现它只存在一个线性弹性区,这与相关文献报道的结果不同.这可以归因于其内部存在着精细、高密度和高强度的细丝微结构.SiC和细丝在外界施加载荷时能够均匀响应.

Abstract:

Silicon carbide(SiC) ceramic foams with a continuously connected open-cell structure were prepared and characterized for their mechanical performance.The apparent densities of the SiC ceramic foams are controlled between 0.4 g/cm~3 and 1.3 g/cm~3,with corresponding compressive strengths ranging from 8 MPa to 50 MPa and flexural strengths from 3 MPa to 30 MPa.Stress-strain curves with only one linearelastic region,which is different from those previous reports on ceramic foams, are obtained by compressive test.This can be attributed to the existence of filaments with fine,dense and high strength microstructures in SiC.The SiC and the filaments can respond homogeneously to applied loading.