【摘要】 采用热压烧结工艺制备了碳纳米管增韧的MoSi2基陶瓷复合材料,根据体系热力学计算确定了材料热压烧结工艺制度,并对合成的CNTs/MoSi2复合材料的力学性能进行了分析。结果表明:以15℃/min的升温速率加热至850℃并保温30 min,进行抽真空脱氧处理,然后加压至20 MPa,并以20℃/min的升温速率升至1 450℃,保温1 h后随炉冷却,即可获得致密无裂纹的CNTs/MoSi2复合材料。材料的断裂韧性可达4.60 MPa.m1/2,比纯MoSi2提高了1倍以上。更多还原

【Abstract】 Molybdenum disilicide ceramic matrix composites reinforced by carbon nanotubes (CNTs) were prepared by hot-pressing. The sintering processing and mechanical properties of the composites were investigated. It is found that a dense and crack-free block of CNTs/MoSi2 composite can be obtained with a processing at 1 450 ℃ for 1 h under a uniaxial load of 20 MPa in vacuum system. The heating rate should be maintained at 15 ℃/min and 20 ℃/min before and after 850 ℃ respectively. The mechanical properties are improved by introduction of CNTs. The fracture toughness is 4.6 MPa.m1/2, which is two times as large as that of monolithic MoSi2.更多还原