CAJ | 학술논문

采用热压烧结方法制备出致密的SiC短纤维和Si_3N_4颗粒复合增强的BAS玻璃陶瓷基复合材料.利用XRD、SEM、TEM和3点弯曲等分析测试手段研究了物相组成、显微结构、界面结构及室温力学性能.结果表明,BAS能有效地促进复合材料的致密化和实现Si_3N_4的α→β相转变.复合材料中的BAS为六方相,SiC短纤维具有热压取向性,与BAS基体之间的界面结合紧密.SiC短纤维和Si_3N_4颗粒对BAS有较为显著的强韧化效果,复合材料的室温弯曲强度和断裂韧性为298 MPa和4.38 M Pa·m~(1/2),比纯六方BAS玻璃陶瓷分别提高了247%和143%.
채용열압소결방법제비출치밀적SiC단섬유화Si_3N_4과립복합증강적BAS파리도자기복합재료.이용XRD、SEM、TEM화3점만곡등분석측시수단연구료물상조성、현미결구、계면결구급실온역학성능.결과표명,BAS능유효지촉진복합재료적치밀화화실현Si_3N_4적α→β상전변.복합재료중적BAS위륙방상,SiC단섬유구유열압취향성,여BAS기체지간적계면결합긴밀.SiC단섬유화Si_3N_4과립대BAS유교위현저적강인화효과,복합재료적실온만곡강도화단렬인성위298 MPa화4.38 M Pa·m~(1/2),비순륙방BAS파리도자분별제고료247%화143%.
Compact silicon carbide fiber-reinforced BAS/Si_3N_4 composite was synthesized by hot-pressing at 1650 ℃under a pressure of 25 MPa for 1 h in 0.1 MPa nitrogen atmosphere. Phase compositions, microstructures, interfacial structures between the fibers and matrix, and the mechanical properties of the composites were studied by means of XRD, SEM TEM and three-point bending methods. The results show that the BAS could benefit densification and partially realize the α→β-Si_3N_4 phase transformation. Hot-pressing orientation of the high modulous silicon carbide fiber was observed in the hexacelsian matrix. Bond trength between the silicon carbide and the BAS matrix was strong. Appearent reinforcement effects by the silicon carbide fiber and the silicon nitride particles were obtained. The flexural strength and the fracture toughness could reach 298 MPa and 4.38 MPa·m~(1/2), respectively, which was increased by 247% and 143% in comparison with that of the BAS glass ceramic.