C/C-SiC-Cu_3Si复合材料的氧化行为

Oxidation behavior of C/C-SiC-Cu_3Si composites

以全网胎炭毡为预制体,采用化学气相渗透法（CVI）制备C/C坯体,然后采用反应熔体浸渗法（RMI）将Cu和Si同时渗入坯体制得C/C-SiC-Cu3Si摩擦材料,研究复合材料的组织结构和氧化行为。结果表明：C/C-SiC-Cu3Si复合材料的物相组成为C、Si、β-SiC和Cu3Si。在不同温度相同时间氧化过程中,在700~1 000℃范围内,Cu3Si、Si和SiC氧化生成微量的SiO2;在1 000~1 300℃范围内,Cu3Si、Si和SiC同时氧化生成SiO2。但在不同时间相同温度氧化过程中,Cu3Si氧化生成SiO2和CuO,部分Si和SiC氧化生成SiO2。这些SiO2和CuO覆在基体表面对内部纤维和基体起到一定的保护作用。

C/C-SiC-Cu3Si composites were fabricated by react melt infiltration for infiltrating Cu and Si into C/C performs that were prepared by chemical vapor infiltration（CVI）.The structures and oxidation behavior of the composites were investigated.The results show that the prepared composites contain C,Si,SiC and Cu3Si.In the non-isothermal oxidation process,Cu3Si,Si and SiC are oxidized into a little SiO2 in the temperature range from 700 ℃ to 1 000 ℃.Cu3Si,Si and SiC are oxidized into SiO2 between 1 000 and 1 300 ℃ at the same time.But for the isothermal oxidation process,Cu 3 Si are reacted with O2 into SiO2 and CuO,and parts of Si and SiC are oxidized into SiO2.The generated SiO2 and CuO covering the surface of substrate can protect the matrix and fiber to a certain extent.