难熔金属炭化物改性基体对炭/炭复合材料抗氧化性能的影响

INFLUENCE OF REFRACTORY CARBIDES SYNTHESIZED IN THE MODIFICATION OF MATRIX ON THE OXIDATION RESISTANT PERFORMANCE OF C/C COMPOSITE

主要对难熔金属改性炭基体的炭/炭复合材料的抗氧化性能进行了较深入的研究。实验的结果表明,在以中间相沥青为基体先驱体、以PAN—CF为增强体的炭/炭复合材料中,采用Ti、W、Zr、Ta、等过渡区金属化合物为添加剂,以Co、Ni为助液相烧结剂,以TiCl_4、ZrOCI_2等为助炭化剂,通过在材料的内部生成多元金属炭化物,形成一种内部的多层次梯度防护体系,较大幅度地提高了炭/炭材料的抗氧化性能,实现了在改性剂添加量2％～3％的情况下,炭/炭材料氧化失重率下降超过80％,在1100℃/h情况下,材料氧化失重小于5％的良好效果。

The effects of refractory carbides which were made from transition metallic Ti, W, Ta, Zr compounds on oxidation resistant performance of C/C composite was discussed in this paper. The experimental results showed that all refractory carbides synthesized in matrix had good oxidation resistant performance and can great reduce oxidation rate of C/C composite. Particularly,TiC-WC-ZrC multi layers carbides crystal demonstrated outsanding oxidation resistant performance, at the condition of the quantity 2%-3% of the modification agent for the loss-weight of the composite was lower than 4. 11% at the condition of 1 100℃/h in air when total 5% addition volume of compounds was put into the matrix and the protected multi layers was formed in the matrix.