石墨粉对LSI法制备C/C-SiC复合材料性能的影响

摘要

Two-dimensional carbon fiber reinforced resin polymer(CFRP)composites with graphite filler added into resin were prepared,which were further pyrolyzed under different temperatures and infiltrated liquid silicon to fabricate C/C-SiC composites. The effect of graphite filler on microstructure,capillary infiltration behavior and flexural properties were investigated.The results show that interface between fiber bounders of C/C composites with graphite filler has no micro-delamination,and bending behavior of C/C composites with graphite filler presents no significant difference compared with C/C materials without graphite filler.However,cap-illary infiltration mass rates of C/C composites are reduced due to graphite filler.Pyrolysis temperature has significant effect on po-rosity,bending strength as well as capillary infiltration behavior of C/C composites. Flexural strength of C/C-SiC composites pre-pared by above mentioned different C/C composites,is 120~130 MPa.%在酚醛树脂中添加石墨粉,采用模压法制备出CFRP材料,在不同温度热解转化为C/C复合材料,然后反应熔渗( LSI)硅制备出C/C-SiC材料,研究了石墨粉对材料的微结构、毛细渗透行为及机械性能的影响。结果表明,热解后C/C材料中的石墨粉和碳基体之间形成了剥离型微裂纹,但层间结合良好,且弯曲性能和未添加石墨粉C/C材料相当,同时石墨粉的添加降低了C/C材料毛细增重速率。热解温度对C/C材料的孔隙率、弯曲强度和毛细渗透行为均有显著影响。不同条件C/C材料硅化后制备的C/C-SiC弯曲强度基本相当,在120~130 MPa,表明热解温度和石墨粉对C/C-SiC材料的弯曲性能没有明显影响。