碳纤维长度以及添加量对碳化硅网状多孔陶瓷性能的影响

Effects of Carbon Fiber Length and Content on Properties of SiC Reticulated Porous Ceramics

为提高有机泡沫浸渍法制备的碳化硅网状多孔陶瓷的抗折强度,采用碳纤维对碳化硅网状多孔陶瓷进行增强。研究了添加剂和碳纤维对碳化硅陶瓷浆料流变性能和触变性能的影响以及碳纤维长度和添加量对试样微观结构、气孔率、耐压强度、抗折强度的影响。结果表明:当分散剂-FS20添加量为0.1%(质量分数),增稠剂-CMC添加量为0.1%(质量分数),粘结剂-CL添加量为0.05%(质量分数)时,碳化硅陶瓷浆料的流变性能和触变性能达到最佳,碳纤维的加入增加了浆料的粘度;另外,随着碳纤维添加量和长度的增加,试样的抗折强度呈现先增大后减小的变化趋势。当碳纤维长度为1 mm且添加量为0.75%(质量分数)时,试样抗折强度达到最大。

In order to improve the flexural strength of SiC reticulated porous ceramics prepared by the polymer sponge replica technique,the carbon fiber was used to enhance SiC reticulated porous ceramics.The effects of additives and carbon fiber on the rheology and thixotropy of SiC ceramics slurry were studied.Furthermore,the influences of length and content of carbon fiber on the microstructure,porosity,compressive strength and flexural strength of SiC reticulated porous ceramics were also investigated.The results show that the SiC ceramics slurry with 0.1%(mass fraction)dispersant-FS20,0.1%(mass fraction)thickness agent-CMC and 0.05%(mass fraction)binder-CL exhibits excellent rheological and thixotropic behavior.The viscosity of slurry increases by adding carbon fiber.In addition,with the increase of carbon fiber content and length,the flexural strength of SiC reticulated porous ceramics first increases and then decreases.When the length and content of carbon fiber are 1 mm and 0.75%(mass fraction)respectively,the flexural strength reaches the maximum.