PET基高能固体推进剂3D打印配方设计与制备

以四氢呋喃共聚醚(PET)基高能固体推进剂为研究对象,设计了以定型助剂改性的PET/硝酸酯(NG/BTTN)为黏合剂体系,高氯酸铵(AP)为固体填料,多官能团脂肪族异氰酸酯(N-100)为固化剂的3D打印推进剂配方。对定型助剂MS在25℃条件下的定型效果、与各组分的相容性以及25,35,45,55℃温度下的流变特性开展了研究,通过仿真模拟确定了温度、喷头直径、压力等3D打印工艺参数的合理范围。结果表明MS与推进剂中与PET/NG/BTTN、AP的相容性较好,并在一定程度上提升了推进剂的安全性能,药浆具有温敏特性,可在25℃达到良好的定型效果,在温度50℃、喷头直径1.2 mm、压力11 kPa的打印参数下,实际打印速率为8 mm·s^-1,首次实现了PET基高能固体推进剂3D打印成型。     

铝基水凝胶的铝/水反应机理研究

为了研究PVA-nAl/HTPB的铝水反应特性,将端羟基聚丁二烯（HTPB）包覆的纳米铝粉（nAl/HTPB）分散于物理交联法制备的聚乙烯醇（PVA）水凝胶中得到聚乙烯醇-nAl/HTPB。通过研究25、40、55、70、85 ℃和100 ℃下PVA-nAl/HTPB复合物在0.1 mol·L^-1 NaOH溶液中的铝水反应及反应后残渣,探究铝水反应机理。结果表明,PVA-nAl/HTPB的最大产氢量和最大产氢速率分别比PVA-nAl高76 mL·g^-1和80 mL·g^-1·min^-1,铝水反应的最终产物为羟基氧化铝（AlO（OH））。     

3,5-二硝氨基-1,2,4-三唑肼盐晶体结构、热性能及在CMDB推进剂中的应用

在甲醇/水溶剂中培养了3,5-二硝氨基-1,2,4-三唑肼盐（HDNAT）单晶,利用X射线单晶衍射仪测定了结构;晶体结构解析表明HDNAT属于正交晶系,空间群为P2（1）,晶胞参数a=0.35976（12） nm,b=0.9348（3） nm,c=1.1833（4） nm,V=0.393.9（2） nm³,Z=2,D_c=1.91 g·cm^-3,μ=0.170 mm^-1,F（000）=230;采用TG-DTG分析了HDNAT的热性能,其分解峰温为193.17 ℃,分解历程为固相直接分解;设计并制备了含HDNAT的改性双基推进剂（CMDB）配方,测试了爆热、比容、密度、特征速度、比冲等能量特性参数和燃烧性能,实测爆热为6042 kJ·kg^-1、比容为638 L·kg^-1、密度为1.767 g·cm^-3、特征速度为1592.3 m·s^-1;Φ50 mm发动机燃烧性能实测结果表明,在15 MPa压强下工作稳定,比冲可达到250.91 s,燃速较RDX-CMDB推进剂提高18.8%以上,但推进剂的部分压强指数超过0.4以上。     

铝基微单元复合燃料在NEPE固体推进剂中的应用

为研究铝基微单元燃料在硝酸酯增塑聚醚（NEPE）固体推进剂中的应用性能,以自制的铝基微单元复合燃料（Al@AP）代替铝粉加入NEPE固体推进剂,以真空定容爆热试验、发动机试验、残渣活性铝测试、高速摄影、单向拉伸试验、工艺性能测试等手段研究了Al@AP对NEPE固体推进剂燃烧、力学、工艺等性能的影响;并对Al@AP在NEPE固体推进剂中的燃烧作用机理进行了分析。结果表明,以19.5%的Al@AP代替FLQT-3 Al后,NEPE固体推进剂的爆热由6039.4 J·g^-1提升至6924.8 J·g^-1,残渣量由28.91 g降至7.64 g,残渣活性铝含量由14.64%降至0.37%,残渣粒径d₅₀由94.12 μm降至24.21 μm,NEPE固体推进剂喷射效率提升,铝粉在燃面停留时间由55 ms缩短至40 ms,且无明显融联团聚现象,且Al@AP对推进剂的燃速、力学、工艺等性能基本无影响。     

PVA/FEVE/CL-20炸药油墨设计、直写成型及其微尺度传爆特性

为考察氟碳树脂（FEVE）在炸药油墨中的应用效果,以聚乙烯醇（PVA）水溶液为水相,FEVE乙酸乙酯溶液为油相,设计了一种新型水包油乳液型黏结体系,并加入亚微米ε-CL-20颗粒,配制CL-20基炸药油墨进行直写技术打印。采用扫描电子显微镜、流变测试仪、X射线衍射仪、撞击和摩擦感度测试仪对打印成型样品进行形貌表征和传爆性能测试。结果表明,PVA/FEVE水包油乳液型黏结剂体系稳定存在时间可达174 h。90%固含量的CL-20的炸药油墨流变性能最佳,具有良好的可打印性。所得直写打印成型样品表面光滑,为多微孔内部结构,CL-20炸药晶型仍为ε型。打印样品的撞击能和摩擦力分别为216 N和4.5 J,相比原料ε-CL-20,撞击感度和摩擦感度分别降低了125%和200%。打印样品的爆速、临界传爆拐角、1 mm线宽临界传爆厚度和方形截面临界传爆尺寸分别为6772 m·s^-1、160°、0.039 mm和0.4 mm×0.4 mm,具有优异的微尺度传爆能力。     

高强度CL-20/HTPE基微尺度传爆药的打印成型及性能表征

为了研制出力学性能优异的微机电系统（MEMS）火工品用微尺度传爆药,以六硝基六氮杂异伍兹烷（CL-20）为主体炸药,以端羟基聚醚（HTPE）/硝化纤维素（NC）为复合黏结体系,以乙酸乙酯为共溶剂,加入一定量的甲苯二异氰酸酯（TDI）设计出一种全溶式炸药油墨,利用喷墨打印技术实现了高精度装药成型,利用异氰酸根与羟基的交联反应实现了微装药力学性能增强。采用电子密度仪、扫描电子显微镜、差示扫描量热仪、X射线衍射仪、纳米压痕仪分别对打印样品的密度、微观形貌、热安定性、炸药晶型和力学性能进行了表征。结果表明,打印样品实测密度为1.70 g·cm^-3,可达最大理论密度的88.54%,打印样品中CL-20由ε晶型转变为β晶型,其热分解表观活化能为173.00 kJ·mol^-1,比原料CL-20提升了13.17 kJ·mol^-1。打印样品弹性模量可高达10.47 GPa,硬度为0.22 GPa,展现了良好的力学性能。喷墨打印装药具有良好的传爆能力,临界爆轰尺寸和爆速分别为1 mm×0.18 mm和8054 m·s^-1。     

宽温域宽应变率下丁羟四组元HTPB推进剂单轴压缩力学行为

为研究丁羟四组元端羟基聚丁二烯（HTPB）推进剂在宽温域宽应变率下的单轴压缩力学行为,基于万能材料试验机、高速液压伺服试验机、分离式霍普金森压杆,结合可程式恒温恒湿试验机等温控手段,开展了宽温域宽应变率下的推进剂单轴压缩力学性能实验,获取了-40,-25,-10,20,50 ℃ 5个温度下10^-4~10³ s^-1应变率的丁羟四组元HTPB推进剂的应力应变曲线,并建立了HTPB推进剂的分段式单轴压缩率温本构关系。结果表明,HTPB推进剂的力学响应存在显著的率温相关性,在任意应变率下其力学响应都呈阶段性变化,即线弹性阶段-非线性屈服阶段-应变软化阶段或应变硬化阶段;且在高应变率下,非线性屈服行为后的应变软化现象明显弱于低、中应变率。此外,高应变率时,随着温度的降低,应力应变曲线的变化速率逐渐减缓;而低、中应变率却恰恰相反,随着温度的降低,应力应变曲线的变化速率逐渐加快。HTPB推进剂的力学强度随着温度的降低显著增大,温度从50 ℃降低至-40 ℃时,HTPB推进剂试件在宽应变率作用下的最大应力从2.2~8.8 MPa增长至约11~22 MPa。同时基于实验数据构建了分段式率温本构关系,发现其在温度较高时拟合效果更好,能够较好地预测HTPB推进剂的力学行为。     

中止燃烧方法模拟固体推进剂动态点火冲击过程（英）

为了研究火箭发动机点火过程中动态冲击对固体推进剂的影响,设计了一个基于中止燃烧的模拟点火冲击装置。该装置由点火螺栓、燃烧室和泄压螺栓组成。金属爆破片安装在泄压螺栓的剪切口处,在点火冲击过程中准确控制泄压压力。模拟点火冲击试验的研究对象是圆环柱体形状的poly(BAMO-THF)/AP/Al固体推进剂试样。p-t曲线表明爆破片的泄压压力与测得的压力一致,其误差在±6%。根据p-t曲线计算增压速率,10 MPa下增压速率达到7000 MPa·s^-1,15 MPa下增压速率达到12000 MPa·s^-1,这远远大于固体火箭实际点火过程中的增压速率。在模拟点火冲击试验后,推进剂试样端面(受损表面)镶嵌的粒子受损,而内侧表面(未损表面)仍保持完整的状态。点火冲击试验后,推进剂试样的压缩强度增加,而压缩强度开始增加时的形变值降低。这说明在模拟点火冲击试验后,推进剂受损表面会进一步受损,力学性能也会发生改变。     

硅烷偶联剂改性α-AlH3材料的制备及其与HMX和CL-20的相容性

为提高α-AlH₃与HMX和CL-20的相容性,选用带有不同有机官能团的硅烷偶联剂对α-AlH₃进行包覆改性。通过X射线衍射仪（XRD）、红外光谱仪（FT-IR）、X光电子能谱（XPS）和扫描电镜（SEM）对包覆改性前后α-AlH₃的结构和形貌进行表征,并考察α-AlH₃和改性后所得材料分别与HMX和CL-20的相容性。结果表明：硅烷偶联剂在不改变α-AlH₃本体结构的基础上,可在其表面形成均匀的包覆层;其中γ-巯丙基三乙氧基硅烷（KH580）包覆改性提高了α-AlH₃热稳定性,使其最高热分解温度提高1.7 ℃,活化能E_a值增加2.21 kJ·mol^-1;γ-氨丙基三乙氧基硅烷（KH550）和γ-甲基丙烯酰氧基丙基三甲氧基硅烷（KH570）改性后,α-AlH₃与HMX混合体系的相容性从3级提升至1级;KH550改性后,α-AlH₃与CL-20混合体系的相容性从4级提升至1级。     

不饱和聚酯包覆层流动及浇注的仿真模拟

固体火箭发动机技术的发展对现有的包覆层生产技术提出了新的挑战,采用热固性树脂作为基体,结合连续自动化包覆技术,可快速得到成型完整、性能优异的包覆层,是近年来较为热门的包覆层生产方法。本研究分析了不饱和聚酯（UPR）包覆层的流动性和浇注条件,通过在Fontana-Kiuna模型基础上引入指数函数,得到匹配的化学流变模型,建立了UPR固化时粘度与时间、温度的函数关系,得到了适合包覆层浇注操作的温度;以Bird-Carreau幂律方程建立UPR流体的本构方程,使用Polyflow软件在前述温度下对恒速模式和恒压模式下UPR包覆层的浇注过程进行模拟,分析了浇注速率、浇注压力对充填完整性的影响,预测了包覆层的填充体积分数分布、流动速率分布和熔接线位置。结果表明,为了保证UPR包覆层浇注完整,浇注温度应该在35 ℃以下,浇注压力应大于1 MPa,入口流速应大于150 mm³·s^-1且小于175 mm³·s^-1。     

Nitrosation and Nitration of Tetraacetyldibenzylhexaazaisowurtzitane

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.     

A Robust Algorithm for Watermarking 2D Vector Maps with Low Shape-Distortions

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.     

Open Rule-setting System Applied to Conceptual Design of Engines

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.     

Research on Linux Network Device Driver

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.     

Improvement and Experiment of the Reamer in Vibra Cutter Against Wave Edge of Titanium Sheet Alloy Parts

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.     

Experimental Study on the Small Flyer Initiating Behavior of Fine-grained Explosives

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.     

Stability of the Third Generation Intensifier under Illumination

The stability under illumination of transmission-mode GaAs photocathode sealed in the third generation intensifier is investigated by use of spectral response testing instruments. The variations of spectral response with the illumination times under weak and intense illumination are compared. The variations of photoemission performance parameters are also characterized. The results show that during initial several weak illuminations photocathode behaves no evident decay and a maximum sensitivity is achieved, while under intense illumination the sensitivity of photocathode begin to decrease largely at the first illumination. The calculated performance parameters show that the variation of surface escape probability with illumination times is a direct cause of instability of photocathode. It is also found that under intense illumination peak wavelength is moved towards short-wave and peak response is decreased, which shows that the ability of long-wave response of photocathode is decreased.     

Algorithm for Multi-laser-target Tracking Based on Clustering Fusion

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.     

Robust Graded Sliding Mode Tracking Control for Low Speed Spinning Ballistic Missiles

The nonlinear dynamic model of spinning ballistic missiles is established during the first boosting phase of the missile. Based on the conventional backstepping sliding mode control and the assumption of a two time-scale separation of missile dynamics, a graded sliding mode controller is designed with two sub-sliding surfaces which have invariability to external disturbances and parameter perturbations, and a matrix which comprises three first order low pass filters is introduced to prevent ＂explosion of terms＂. Owing to the upper bounds of the uncertainties are difficult to obtain in advance, adaptive laws are introduced to estimate the values of the uncertainties in real-time. Eventually, the numerical simulation results given to show the proposed controller can ensure the steady flight of missiles.     

A Study on the Estimation of Aeroheating upon the Warhead Nose at Supersonic Speed

An expression for estimating the aeroheating on a warhead nose at different supersonic speeds is proposed by incorporating CFD （computational fluid dynamics） and the least-square method. Compared with the traditional estimation formula, the expression is more accurate, convenient and can be used in the optimized design of warheads. The error from the result obtained in the test of a ball cartridge flight is less than 3 %. It satisfies the engineering requirements.