Molybdenum disilicide(MoSi_2) based composites with various contents of carbon nanotubes(CNTs) were fabricated by spark plasma sintering(SPS) in vacuum under a pressure of 25 MPa.The composites obtained under a sinter...Molybdenum disilicide(MoSi_2) based composites with various contents of carbon nanotubes(CNTs) were fabricated by spark plasma sintering(SPS) in vacuum under a pressure of 25 MPa.The composites obtained under a sintering temperature of 1500 °C and time of 10 min exhibited optimum mechanical properties at room temperature in terms of fracture toughness and transverse rupture strength.MoSi_2 based composite with 6.0% CNTs(volume fraction) had the highest fracture toughness,transverse rupture strength and hardness,which were improved by about 25.7%,51.5% and 24.4% respectively,as compared with pure MoSi_2.A Mo_(4.8)Si_3C_(0.6) phase was detected in CNTs/MoSi_2 composites by both X-ray diffraction(XRD) method and microstructure analysis with scanning electron microscopy(SEM).It is believed that the fine grains and well dispersed small Mo_(4.8)Si_3C_(0.6) particles had led to a higher hardness and strength of CNTs/MoSi_2 composites because of their particle pullout,crack deflection and micro-bridging effects.展开更多
基金Project(51371155)supported by the National Natural Science Foundation of ChinaProject(2014H0046)supported by the Key Science and Technology Project of Fujian Province,China+2 种基金Project(3502Z20143036)supported by the Scientific Research Fund of Xiamen,ChinaProject(JB13149)supported by the Education Department Science and Technology Project of Fujian Province,ChinaProject(2012D131)supported by the Natural Science Foundation Guidance Project of Fujian Province,China
文摘Molybdenum disilicide(MoSi_2) based composites with various contents of carbon nanotubes(CNTs) were fabricated by spark plasma sintering(SPS) in vacuum under a pressure of 25 MPa.The composites obtained under a sintering temperature of 1500 °C and time of 10 min exhibited optimum mechanical properties at room temperature in terms of fracture toughness and transverse rupture strength.MoSi_2 based composite with 6.0% CNTs(volume fraction) had the highest fracture toughness,transverse rupture strength and hardness,which were improved by about 25.7%,51.5% and 24.4% respectively,as compared with pure MoSi_2.A Mo_(4.8)Si_3C_(0.6) phase was detected in CNTs/MoSi_2 composites by both X-ray diffraction(XRD) method and microstructure analysis with scanning electron microscopy(SEM).It is believed that the fine grains and well dispersed small Mo_(4.8)Si_3C_(0.6) particles had led to a higher hardness and strength of CNTs/MoSi_2 composites because of their particle pullout,crack deflection and micro-bridging effects.