聚合物浸渍裂解法制备C/C-ZrC复合材料及其性能

本文以低密度C/C复合材料为坯体,有机锆聚合物为前驱体,采用聚合物浸渍裂解法(PIP)制备C/C-ZrC复合材料,并对其微观结构、力学性能、烧蚀性能以及烧蚀机理进行了研究。结果表明ZrC在材料内分布均匀,密度为2.05g·cm~(-3)的C/C-ZrC复合材料其弯曲强度为89.70MPa,呈脆性断裂。经氢-氧焰烧蚀150s后其线烧蚀率为-2.2×10~(-3)mm·s~(-1),质量烧蚀率为-1.0×10-3g·s~(-1),远低于密度为1.86g·cm~(-3)的C/C复合材料(线烧蚀率:4.4×10~(-3) mm·s~(-1),质量烧蚀率:7.5×10~(-4)g·s~(-1));在烧蚀的过程中,ZrC表现出优先氧化,同时生成的ZrO_2阻挡层能有效阻挡热量的传递和氧气的渗透,提高了材料的抗烧蚀性能。

Preparation and Properties of C/C-ZrC Composites by Precursor Infiltration and Pyrolysis

C/C-ZrC composites were prepared by precursor infiltration and pyrolysis method (PIP) using organic zirconium as precursor,and low density carbon/carbon composites as performs.The microstructure,mechanical properties,ablation behavior and the anti-ablation mechanism were investigated.The results show that the ZrC phase is uniformly distributed in the materials,the flexural strength of the C/C-ZrC composites with a density of 2.05g·cm-3 is 89.70MPa,and it belongs to the brittle fracture.The linear and mass ablation rates of C/C-ZrC composites after oxy-hydrogen flame ablation for 150s are-2.2 × 10 3mm· s-1 and-1.0 × 10-3g·s-1,respectively,which is much lower than that of C/C composites (linear ablation rates:4.4× 10 a mm·s 1;mass ablation rates:7.5×10 4g·s 1).ZrC exhibits preferential oxidation in the process of ablation.Meanwhile,the formation of the ZrO2 layer can effectively prohibit the heat transfer and infiltration of oxygen,and improve the anti-ablation performance of C/C.