Various thermal protective ablative materials (TPAM) have been extensively studied. However, there are few reports on the thermal stability, the ablation properties and ceramisation of vitreous silica fabric reinforced boron phenolic resin composites with an incorporation of MoSi2(VMBPR) and their bending strength after ablation. At this work, the above performances of the composites were characterised and analysed. Results reveal that the addition of MoSi(2)decreases the graphitisation temperature of glass carbon of BPR pyrolysis, promoting the formation of a more ordered structure of the glassy carbon during pyrolysis. Furthermore, compared with the composites without MoSi2(VBPR), the linear and the mass ablation rate of VMBPR composites decrease by about 94.46% and 39.09%, and its room temperature bending strength after static ablation at 1400 degrees C for 20 min is more than twice that of the fused fibre aggregation formed by VBPR composites. This is attributed to the ceramisation reaction of VMBPR composites at high temperature.

With the development of rocket and aerospace technology in recent decades, people have put forward higher requirements on the heat resistance and ablation performance of thermal protection materials. In this paper, zirconia fibre hybrid alumina fibre/boron phenolic (ZA/BPF) ceramifiable composites, based on ceramic fillers of MgO, Al2O3, SiC and mica-modified boron phenolic resin matrix, were prepared with different hybrid fibre contents (5, 10, 15, 20, 25, 30 wt-%) by hot compression moulding. The result shows that fibre contents have little effect on the ablation resistance of composite materials which all have a low linear ablation rate below 0. 01 mm s(-1). When the fiber content is 25%, the ZA/BPF composite reaches the highest bending strength 48. 86 MPa and 15. 57 MPa before and after sintering respectively. It is showed by the SEM results that too high and too low fibre content would both lead to poor bonding between resin and fibre interfaces.