Effect of surface structure unit of 3D needled carbon fiber preform on the ablation improvement of "Z-pins like" V-0.9-Si-0.1 rod for C/C-ZrC-SiC

The effects of the different surface structure units due to "Z-pins like" V-0.9-Si-0.1 rods on the improvement of the ablation resistance of C/C-ZrC-SiC were investigated. The ablation properties of the V-0.9-Si-0.1 rods acting on the surface of short-cut fibre web and laminated layers were tested for different ablation times. The results showed that although the ablation resistances of the composites with different surface structure units improved using neoteric "Z-pins like" V-0.9-Si-0.1 rods as polybasic multiphase oxide compensators, the improvement mechanisms were different. For an ablation time less than 180 s, the rods perpendicular to the short-cut fibre web resulted in a higher improvement in ablation resistance by a liquid/gas multicomponent oxide compensation mechanism. Whereas, for an ablation time over 180 s, the rods perpendicular to the laminated layers resulted in a higher improvement because of the oxide melting erosion experienced by the short-cut fibre web surface.