(1. 大連理工大學(xué) 工業(yè)裝備結(jié)構(gòu)分析國家重點實驗室，大連 116024；
2. 大連理工大學(xué) 航空航天學(xué)院，遼寧省空天飛行器前沿技術(shù)重點實驗室，大連 116024)
摘 要: 以不同溫度熱處理纖維為增強體，以酚醛樹脂為碳基體先驅(qū)體，利用先驅(qū)體浸漬裂解(PIP)工藝制備碳纖維增強碳基(C/C)復(fù)合材料。微觀形貌觀察發(fā)現(xiàn)纖維熱處理能夠改變C/C多孔體(經(jīng)過一次裂解后)的孔隙尺寸和分布模式。力學(xué)性能測試發(fā)現(xiàn)，隨著熱處理溫度提高，C/C復(fù)合材料的力學(xué)性能不斷提高，對纖維進行1200 ℃熱處理后，C/C彎曲強度和層間剪切強度分別提高了1.58倍和1.21倍，同時失效模式由脆性斷裂轉(zhuǎn)變?yōu)榧偎苄詳嗔选？寡趸阅苎芯堪l(fā)現(xiàn)，600 ℃熱處理纖維增強材料的抗氧化性能提升，而更高溫度的纖維熱處理導(dǎo)致材料抗氧化性能下降。C/C復(fù)合材料性能變化的主要原因是熱處理降低纖維表面的反應(yīng)活性，使得C/C獲得結(jié)合適宜的纖維/基體界面。
關(guān)鍵字: C/C復(fù)合材料；熱處理；力學(xué)性能；抗氧化性能
（1. State Key Laboratory of Structural Analyses for Industrial Equipment, Dalian University of Technology, Dalian 116024, China;
2. School of Aeronautics and Astronautics,Liaoning Provincial Key Laboratory of Advanced Technology for Aerospace Vehicle,Dalian University of Technology, Dalian 116024, China）
Abstract:Carbon fiber reinforced carbon matrix composites (C/C) were prepared by precursor impregnation pyrolysis (PIP) method, carbon fibers heat-treated at different temperatures were used as reinforcement, phenolic resin was used as carbon precursor. The results show that the size and distribution pattern of pores in porous preform (after primary cracking) are changed, according to micromorphology observation. Mechanical properties of C/C composites are improved with the increase of heat treatment temperature. Flexural strength and interlaminar shear strength of C/C increase by 1.58-fold and 1.21-fold after fibers heat-treated at 1200 ℃. With the heat treatment temperature rising, the fracture mode of C/C is changed from brittle to pseudoplastic. Oxidation resistance of 600 ℃ heat-treated fiber reinforced composite is improved, while those of 1200 ℃ and 1500 ℃ heat-treated fiber reinforced composites decrease. The property of C/C is changed because heat treatment reduces the surface activity of fibers, so C/C composite has a suitable interface.
Key words: C/C composites; heat treatment; mechanical property; oxidation resistance
