The properties and structures of 3D-Cf/SiC composites prepared by rapid precursor infiltration pyrolysis process were studied. PCS solution was infiltrated into 3D-carbon fiber perform in vacuum, then these performs were dried at room temperature and pyrolyzed with three kinds of heating rate, 3 900 min, 1 500 min and 1 000 min respectively. The distinction of 3D-Cf/SiC samples fabricated at three kinds of heating rate was not obvious. Bending strength of sample at 1 000 min heating rate was 762.5 MPa, and a little better than the others. Three samples at various heating rate had similar micro-graph of fracture surface and fracture toughness. The research results show that mechanics performances of Cf/SiC composites did not decrease when heating rate was properly increased.%研究了不同升温裂解速率对PIP工艺制备的3D-Cf/SiC复合材料性能的影响.采用了3种升温制度,每次裂解时间分别为3 900 min、1 500 min和1 000 min.实验发现3种升温制度下制备的材料的力学性能差别比较小,1 000 min裂解制备的试样的弯曲强度高达762.5 MPa,其弯曲强度和断裂韧性常数还略高于另外2种.不同升温速率下试样断口的SEM照片均显示很长的纤维拔出,增韧效果显著.研究表明,适当提高升温速率并没有降低Cf/SiC复合材料的力学性能.
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