Railgun materials play an important role in electromagnetic launch,and its performance has great effect on the shot-efficiency and lifetime of the launcher.In this paper,the effect of shots number on the performance o...Railgun materials play an important role in electromagnetic launch,and its performance has great effect on the shot-efficiency and lifetime of the launcher.In this paper,the effect of shots number on the performance of multiple launch railgun material under high current conditions is studied by metallurgical analysis.The metallographys of kinds of rails'surface at various locations are observed,and the details of damage zones at different positions are analyzed.The results indicate that molten aluminum from the armature deposits on the rail surface to form a thin film.The deposited film becomes thicker and multi-layered with the increase of shots number.When the velocity is greater than 2 km /s,the gouge phenomenon always appears.The gouge volume of material is measured by 3D laser image and the qualitative observations of the damage are obtained.The evidences show that gouge phenomenon mainly causes by the kinetic energy of the armature and it is related to the shear strength of rail materials closely.By the addition of nano-sized ceramic powders,the shear strength of rail materials increases,the volume of gouge decreases during multiple launches.展开更多
Recent progress on the application of laser-induced breakdown spectroscopy (LIBS) for metallurgical analysis particularly achieved by Chinese research community is briefly reviewed in this article. The content is ma...Recent progress on the application of laser-induced breakdown spectroscopy (LIBS) for metallurgical analysis particularly achieved by Chinese research community is briefly reviewed in this article. The content is mainly focused on the progress in experimental research and calibration methods toward LIBS applications for metallurgical online analysis over the past few years. Different experiment setups such as single-pulse and double-pulses LIBS schematics are introduced. Various calibration methods for different metallic samples are presented. Quantitative results reported in the literature and obtained in the analysis of various samples with different calibration methods are summarized. At the last section of this article, the difficulties of LIBS application for molten metal analysis in a furnace are discussed.展开更多
基金Sponsored by the National Basic Research Program(Grant No.2010CB731600)
文摘Railgun materials play an important role in electromagnetic launch,and its performance has great effect on the shot-efficiency and lifetime of the launcher.In this paper,the effect of shots number on the performance of multiple launch railgun material under high current conditions is studied by metallurgical analysis.The metallographys of kinds of rails'surface at various locations are observed,and the details of damage zones at different positions are analyzed.The results indicate that molten aluminum from the armature deposits on the rail surface to form a thin film.The deposited film becomes thicker and multi-layered with the increase of shots number.When the velocity is greater than 2 km /s,the gouge phenomenon always appears.The gouge volume of material is measured by 3D laser image and the qualitative observations of the damage are obtained.The evidences show that gouge phenomenon mainly causes by the kinetic energy of the armature and it is related to the shear strength of rail materials closely.By the addition of nano-sized ceramic powders,the shear strength of rail materials increases,the volume of gouge decreases during multiple launches.
基金Acknowledgements We acknowledge the financial support from the National Natural Science Foundation of China (Grant No. 11075184) and the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. Y03RC21124).
文摘Recent progress on the application of laser-induced breakdown spectroscopy (LIBS) for metallurgical analysis particularly achieved by Chinese research community is briefly reviewed in this article. The content is mainly focused on the progress in experimental research and calibration methods toward LIBS applications for metallurgical online analysis over the past few years. Different experiment setups such as single-pulse and double-pulses LIBS schematics are introduced. Various calibration methods for different metallic samples are presented. Quantitative results reported in the literature and obtained in the analysis of various samples with different calibration methods are summarized. At the last section of this article, the difficulties of LIBS application for molten metal analysis in a furnace are discussed.