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1.
利用感应等离子体作为热源对碳化钨粉进行球化技术研究,通过工艺参数的设计实现粉体中球形粉体的比例大于85%,同时比较球化处理前后粉体的粒度、氧含量、形貌等指标。结果表明,采用等离子法制备的碳化钨粉体材料形貌呈标准球形,氧含量显著降低,通过工艺参数的调整能够较精确地实现粒度范围的控制。  相似文献   

2.
为实现对感应等离子技术制备电容器级钽粉粒度、形貌的控制,进行改变等离子工艺参数的粉体制备工艺试验,研究冷却气体流量、送入粉体的进口位置、等离子气氛对粉体粒度及其形貌的影响。结果表明,感应等离子工艺参数的变化可以显著改变制备粉体的性能。制备的钽粉全部为球形,感应等离子技术可以完成纳米级电容器钽粉的制备。  相似文献   

3.
感应等离子纳米钽粉制备技术研究   总被引:2,自引:0,他引:2  
为了实现对感应等离子技术制备电容器级钽粉粒度、形貌的控制,进行了改变等离子工艺参数的粉体制备工艺试验,试验中考察等离子功率、送粉速率对制备粉体的粒度、粒度分布及其形貌的影响。试验结果表明:在一定等离子体功率下,随着送粉速率的增加,粉体平均粒径增加,比表面积下降;在一定送粉速率下,随着等离子体功率的增加,粉体平均粒径减小,比表面积增加。感应等离子工艺参数的变化可以改变制备粉体性能。  相似文献   

4.
以链烷醇胺为分散剂,用对苯二酚C6H4(OH)2还原硝酸银,通过调节硝酸银浓度、还原剂配比以及分散剂添加量等工艺参数实现对银粉粒径的控制。用扫描电镜(SEM)表征银粉的形貌、球形度和分散性;用激光粒度分布仪测试不同粒径银粉的粒度分布;参照GB 5162-85测试不同粒径粉体和级配后粉体的振实密度。结果表明:制备的银粉表面粗糙度低、球形度和密实度高,其流动性随粒径的减小变差,振实密度随之减小。合适的颗粒级配能有效提高粉体的振实密度,其最大值达到4.75 g/cm^3。  相似文献   

5.
利用连续式、感应等离子体技术进行电容器级纳米钽粉制备技术研究,对制备的粉体进行比表面积测试、扫描电镜的形貌观察和粒度分布的统计。结果表明:感应等离子体技术制备的钽粉形貌为球形;手套箱粉体比表面积最高达到40 m2/g以上;随原料粉体粒径的减小,分散性越好,粉体与感应等离子体的能量耦合程度越高。  相似文献   

6.
以Pb(NO3)2和SnCl4·5H2O为主要原料,采用溶胶共沉淀法制备超细粉末PbSnO3,通过XRD、激光粒度分析和SEM表征粉体的结构、粒度以及粉体的形貌。通过正交试验对试验条件进行优化,结果表明:在Pb(NO3)2溶液的浓度为0.1mol/L、溶液的pH值为8~9、PEG-200的加入质量分数为5%、反应温度为65℃的最优条件下制得PbSnO3粉体为球形,且分散性较好。  相似文献   

7.
含能快递     
何璇 《含能材料》2018,26(8):637-637
正美国圣地亚国家实验室研制了一种高均匀度的CL-20纳米微球美国圣地亚国家实验室设计了一种用表面活性剂辅助的自组装工艺,研制出均匀球形微米级颗粒的CL-20重结晶新方法。结合x射线衍射、拉曼光谱结果表明,球形CL-20球形颗粒晶型为斜方晶系β?phase。证实了表面活性剂在控制CL-20晶体形貌过程中起着重要作用。通过研究得到CL-20纳米微球,其单分散性质及较小的颗粒度(亚微米),有效降低了CL-20冲击波感度,有利于促进CL-20应用。  相似文献   

8.
为提高分子钙钛矿含能材料(DAP-4)的装药工艺安全性,采用同轴型液滴微流控技术,改变黏结剂聚叠氮缩水甘油醚(GAP)和硝化纤维素(NC)的复合比例(占DAP-4质量的2%)实现了DAP-4基含能复合微球的球形化造粒。通过扫描电镜、X射线衍射仪、差热扫描量热仪、热失重分析仪、高速摄影、撞击感度测试仪和摩擦感度测试仪等系统测试和分析了样品的宏微观形貌、晶体结构、热性能、燃烧性能、机械感度等。结果表明:黏结剂GAP与NC的比例为4∶1时,DAP-4基复合微球(GN41)的球形化效果最好;对DAP-4进行球形化造粒后不会改变其晶体结构,热分解峰温略有提前;DAP-4基复合微球的燃烧时间比原料有轻微延长,总体依然表现出非常平稳的持续燃烧,保留了其优异的燃烧性能;GN41微球在降低机械感度的同时显著改善了流动性,提高了装药工艺安全性。  相似文献   

9.
含能材料晶体的粒度和形貌对其性能影响较大,为了研究1,1-二氨基-2,2-二硝基乙烯(FOX-7)炸药晶体形貌、粒度与其热分解性能的关系,采用溶剂-非溶剂法制备得到了不同形貌、粒度的FOX-7炸药颗粒。使用扫描电子显微镜、X射线衍射仪、差示扫描量热仪和撞击感度测试仪分别对FOX-7炸药的晶体形貌、粒度、晶型、热分解性能和安全性能进行了表征和测试。结果表明,通过改变降温速率、搅拌速率等工艺条件,可以得到海胆形、球形、花状和块状等不同形貌的FOX-7炸药颗粒,所制备的FOX-7炸药晶型与原料一致,均为α型;粒度和形貌对FOX-7分子内氢键的断裂和共轭体系的破坏影响较大,球形形貌有利于提高FOX-7的热分解温度;同一形貌的FOX-7样品,粒径越大,热稳定性越好。在粒径为几十微米的FOX-7样品中,球形形貌的FOX-7样品安全性能最好。  相似文献   

10.
为了调控高聚合物黏结炸药(PBXs)的形貌、粒径分布和涂层包覆效果,采用高灵敏度的液滴微流控技术制备了TATB/F2602微球。研究了黏结剂含量和流量大小对TATB/F2602微球的形貌和粒径的影响。通过扫描电镜、X射线衍射、比表面积、DSC和TG等测试方法,系统研究了微球样品的形貌、结构、成分和热行为。结果表明:黏结剂含量为5%时微球具有光滑表面、规则球形形状和高单分散性,平均圆形度为0.921(跨度为0.040);通过调控流量比逐渐增大,微球样品D50从51.73μm减小到44.31μm,且粒径分布窄(跨度小于0.4);氟橡胶(F2602)均匀分布于TATB微球内部和表面,均匀地包覆TATB颗粒使微球样品热分解延后4.08℃;与原料TATB相比,球形化过程使TATB/F2602真密度增加到1.9780 g·cm-3。液滴微流控技术可以有效调控炸药微球的形貌和粒径,为高聚物黏结炸药的球形化制备提供参考。  相似文献   

11.
Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.  相似文献   

12.
The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS (geographical information system) data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.  相似文献   

13.
Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.  相似文献   

14.
By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux (kernel version 2.6.11 ) is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.  相似文献   

15.
For measuring velocity and impacting position of single fragment of warhead, a non-contact measuring method is proposed, in which a six-light-screen array, a position indicator, a multi-channel chronograph and a computer are used.The principle of measurement is described. The key device of the system is a light screen array sensor which consists of six light screens allocated with certain geometrical parameters. When the fragment flies through the light screen array, the time of passing through each of the screens is recorded by the multi-channel chronograph. According to the time data and the geometrical parameters of the array, the velocity vector and the location of the fragment can be calculated immediately. The presented method can be used to locate the fragment and to measure the real velocity on its flying direction. It can also be used to measure the velocity of a fragment swarm after the system is engineered further.  相似文献   

16.
阐述了数码电子雷管中,点火药剂细结晶三硝基间苯二酚铅(LTNR)的制备工艺;从点火药剂的种类、加入黏合剂的质量分数、桥丝直径、点火头的电阻值、防潮漆的蘸涂等方面对点火头性能的影响因素进行了探讨;通过震动试验、并联起爆试验、延期精度检测与考核,试验结果表明:一次性合成的细结晶LTNR是制造数码电子雷管点火头较为理想的点火药剂,按技术要求生产的点火头性能指标能够满足行业标准要求。  相似文献   

17.
By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly.  相似文献   

18.
The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite.  相似文献   

19.
Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective.  相似文献   

20.
A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same.  相似文献   

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