为了制备较高膨胀容积的膨胀石墨,研究了以50目、80目天然石墨为原料,以高锰酸钾为氧化剂,硫酸做插层剂,用化学氧化法制备膨胀石墨时,氧化剂、插层剂的用量以及酸浓度等因素对膨胀石墨膨胀容积的影响;测定了膨胀温度对膨胀容积的影响。...为了制备较高膨胀容积的膨胀石墨,研究了以50目、80目天然石墨为原料,以高锰酸钾为氧化剂,硫酸做插层剂,用化学氧化法制备膨胀石墨时,氧化剂、插层剂的用量以及酸浓度等因素对膨胀石墨膨胀容积的影响;测定了膨胀温度对膨胀容积的影响。通过正交实验,确定获得最大膨胀容积的最佳实验条件。实验结果表明:50目原料石墨的最佳条件为硫酸与原料石墨的液∶固=5∶1,KMn O4∶C=0.15∶1,硫酸浓度为50%(均为质量比),室温下反应时间为30 min,所得产品的膨胀容积为370 m L/g;80目原料石墨的最佳条件为硫酸与原料石墨的液:固=1.5∶1,KMn O4∶C=0.18∶1,硫酸浓度为73%(均为质量比),室温下反应时间为40 min,所得产品的膨胀容积为280 m L/g。原料石墨及可膨胀石墨的X-射线及电子能谱分析,证实了硫酸插层反应的成功性,两种原料制得可膨胀石墨的最佳膨胀温度均为900℃。展开更多
Polymer bonded explosive(PBX)formulations were successfully prepared in the laboratory scale containing 1,1-diamino-2,2-dinitroethene(FOX-7)and hexogen(RDX)as brisant high explosives and different binder types of poly...Polymer bonded explosive(PBX)formulations were successfully prepared in the laboratory scale containing 1,1-diamino-2,2-dinitroethene(FOX-7)and hexogen(RDX)as brisant high explosives and different binder types of polyurethane(PU)based on glycidyl azide polymer(GAP) and hydroxyl-terminated polybutadiene(HTPB) as an energetic and inert polymeric binder respectively.Casting technique was used for the preparation of different PBX formulations based on FOX-7/RDX and PU(GAP/HTPB)with 14% binder.The sensitivity to different initial impulses and performance characteristics of the explosive and lethal zone of the tested controlled fragmentation warhead by the fragmentation warhead assessment test(arena test)were studied,in which the arena test was carried out with a controlled fragmentation warhead made from Ck45 steel,with dimensions(100 mm length,30 mm outer diameter and 3 mm thickness).Results show that PBXGF4 has lower sensitivity to impact and heat than those of PBXGR4 by 188.4% and 3.2% respectively.Its friction sensitivity is the same as that of PBXGR4.It has better performance,in which detonation velocity increases by 2.1% and brisance increases by 0.5% when compared with those of PBXGR4.It was concluded that PBXGF4 which based on FOX-7 bonded with PU/GAP matrix has good characteristics as PBX,specially in the sensitivity to impact and can be applied for replacing PBXs based on RDX in the advanced PBXs for low sensitive fragmentation warheads.展开更多
The Cu-10 %Fe-1.5 %Ag in situ composite with high strength, high conductivity and low cost was prepared, and its hot deformation behavior was investi- gated by isothermal compression test with true strain of 0.69, tem...The Cu-10 %Fe-1.5 %Ag in situ composite with high strength, high conductivity and low cost was prepared, and its hot deformation behavior was investi- gated by isothermal compression test with true strain of 0.69, temperature range of 750-950℃ and strain rate of 0.002-1.000 s-1. The flow stress-strain response shows the characterization of dynamic recrystallization （DRX）, and the peak stress increases gradually with deformation tem- perature decreasing and strain rate increasing. The defor- mation activation energy of the composite for DRX is calculated as 241.864 kJ.mo1-1. The constitutive relation of the composite was got by Arrhenius equation. Further- more, according to the dynamic material modeling and Kumar-Prasad＇s instability criteria, the processing map was constructed and the unsafe regions for hot deformation were analyzed. Based on the processing map and microstructural evolution, the optimal parameter range for hot deformation processing is 750-863℃ at the strain rate of 0.002-0.013 s-1.展开更多
文摘为了制备较高膨胀容积的膨胀石墨,研究了以50目、80目天然石墨为原料,以高锰酸钾为氧化剂,硫酸做插层剂,用化学氧化法制备膨胀石墨时,氧化剂、插层剂的用量以及酸浓度等因素对膨胀石墨膨胀容积的影响;测定了膨胀温度对膨胀容积的影响。通过正交实验,确定获得最大膨胀容积的最佳实验条件。实验结果表明:50目原料石墨的最佳条件为硫酸与原料石墨的液∶固=5∶1,KMn O4∶C=0.15∶1,硫酸浓度为50%(均为质量比),室温下反应时间为30 min,所得产品的膨胀容积为370 m L/g;80目原料石墨的最佳条件为硫酸与原料石墨的液:固=1.5∶1,KMn O4∶C=0.18∶1,硫酸浓度为73%(均为质量比),室温下反应时间为40 min,所得产品的膨胀容积为280 m L/g。原料石墨及可膨胀石墨的X-射线及电子能谱分析,证实了硫酸插层反应的成功性,两种原料制得可膨胀石墨的最佳膨胀温度均为900℃。
文摘Polymer bonded explosive(PBX)formulations were successfully prepared in the laboratory scale containing 1,1-diamino-2,2-dinitroethene(FOX-7)and hexogen(RDX)as brisant high explosives and different binder types of polyurethane(PU)based on glycidyl azide polymer(GAP) and hydroxyl-terminated polybutadiene(HTPB) as an energetic and inert polymeric binder respectively.Casting technique was used for the preparation of different PBX formulations based on FOX-7/RDX and PU(GAP/HTPB)with 14% binder.The sensitivity to different initial impulses and performance characteristics of the explosive and lethal zone of the tested controlled fragmentation warhead by the fragmentation warhead assessment test(arena test)were studied,in which the arena test was carried out with a controlled fragmentation warhead made from Ck45 steel,with dimensions(100 mm length,30 mm outer diameter and 3 mm thickness).Results show that PBXGF4 has lower sensitivity to impact and heat than those of PBXGR4 by 188.4% and 3.2% respectively.Its friction sensitivity is the same as that of PBXGR4.It has better performance,in which detonation velocity increases by 2.1% and brisance increases by 0.5% when compared with those of PBXGR4.It was concluded that PBXGF4 which based on FOX-7 bonded with PU/GAP matrix has good characteristics as PBX,specially in the sensitivity to impact and can be applied for replacing PBXs based on RDX in the advanced PBXs for low sensitive fragmentation warheads.
基金financially supported by the National Natural Science Foundation of China(No.50571035)the National High-Tech Research and Development Project (No.2006AA03Z528)
文摘The Cu-10 %Fe-1.5 %Ag in situ composite with high strength, high conductivity and low cost was prepared, and its hot deformation behavior was investi- gated by isothermal compression test with true strain of 0.69, temperature range of 750-950℃ and strain rate of 0.002-1.000 s-1. The flow stress-strain response shows the characterization of dynamic recrystallization （DRX）, and the peak stress increases gradually with deformation tem- perature decreasing and strain rate increasing. The defor- mation activation energy of the composite for DRX is calculated as 241.864 kJ.mo1-1. The constitutive relation of the composite was got by Arrhenius equation. Further- more, according to the dynamic material modeling and Kumar-Prasad＇s instability criteria, the processing map was constructed and the unsafe regions for hot deformation were analyzed. Based on the processing map and microstructural evolution, the optimal parameter range for hot deformation processing is 750-863℃ at the strain rate of 0.002-0.013 s-1.
