A tightly focused femtosecond Ti:sapphire laser pulse is used to initiate micro-explosions on the surface and internal to an Fe:LiNb03 crystal. The resulting structure is morphologically different from that induced in...A tightly focused femtosecond Ti:sapphire laser pulse is used to initiate micro-explosions on the surface and internal to an Fe:LiNb03 crystal. The resulting structure is morphologically different from that induced in an isotropic sample such as fused silica. The regular pyramid and irregular pyramid craters on the surface of the sample are produced at different positions of focal points. The craters suggest vaporization of materials in the process of micro-explosion due to the expansion of high temperature plasma. The embossment pyramids on the surface present the dynamical process of large volume material displacements under high temperature and pressure, and recrystallization of anisotropy crystal materials.展开更多
The effect of mineral oil on the mechanical properties and fractographs of Fe3(Al,Cr,Zr) in termetallic alloy has been investigated. The results show that the tensile ductility of the Fe3(Al,Cr,Zr) alloy tested in oil...The effect of mineral oil on the mechanical properties and fractographs of Fe3(Al,Cr,Zr) in termetallic alloy has been investigated. The results show that the tensile ductility of the Fe3(Al,Cr,Zr) alloy tested in oil is comparable with the results obtained in oxygen and is in sensitive to strain rate. The fracture mode of the Fe3(Al,Cr,Zr) alloy treated at 700℃/1.5 h and tested in oil, is cleavage and with dimples in some areas.展开更多
文摘A tightly focused femtosecond Ti:sapphire laser pulse is used to initiate micro-explosions on the surface and internal to an Fe:LiNb03 crystal. The resulting structure is morphologically different from that induced in an isotropic sample such as fused silica. The regular pyramid and irregular pyramid craters on the surface of the sample are produced at different positions of focal points. The craters suggest vaporization of materials in the process of micro-explosion due to the expansion of high temperature plasma. The embossment pyramids on the surface present the dynamical process of large volume material displacements under high temperature and pressure, and recrystallization of anisotropy crystal materials.
文摘The effect of mineral oil on the mechanical properties and fractographs of Fe3(Al,Cr,Zr) in termetallic alloy has been investigated. The results show that the tensile ductility of the Fe3(Al,Cr,Zr) alloy tested in oil is comparable with the results obtained in oxygen and is in sensitive to strain rate. The fracture mode of the Fe3(Al,Cr,Zr) alloy treated at 700℃/1.5 h and tested in oil, is cleavage and with dimples in some areas.
基金Supported by the National Natural Science Foundation of China under the Grant No 60377003. The authors thank Professor Yuheng Xu at Harbin Institute of Technology for providing theZn:Fe:LiNb03 crystal.