钨合金穿甲弹芯变形缺陷的产生形式和形成力学分析

在分析高比重钨合金弹芯挤压变形缺陷产生形式的基础上,利用钨合金变形体塑性区内的速度场分布,推导了变形钨合金弹芯形成内部破裂和表面破裂条件的力学判据,并绘制了两种变形缺陷的力学判据曲线图.试验结果表明,该力学判据将为合理制定液力挤压变形工艺参数、设计优化工模具结构、预测挤压变形缺陷和提高挤压制品质量提供重要的理论依据.     

某高膛压钨合金穿甲弹断裂原因分析与改进研究

通过对比试验法证实了某高膛压钨合金穿甲弹弹尾断裂主要在于弹尾本身强度安全裕度不足，重点从尾部质量过大、材料性能、应力环境、强度校核中所忽略的因素等关键环节对发射强度的影响进行了系统的分析，同时对以真空热处理工艺方法改善提高弹芯尾部材料的综合机械性能为主方案进行研究，较好地解决了尾部断裂问题。     

极限穿透速度与靶板材料动态屈服强度

以钨球侵彻装甲板试验研究结果为依据，运用牛顿第二定律，对不同弹靶条件下靶板材料的动态屈服强度进行了计算．结果表明，靶板材料的动态屈服强度并非常数，而与靶板厚度有直接关系，进而对极限穿透速度计算公式中靶板材料动态屈服强度一项进行修正，采用修正公式可获得与试验数据相符的结果．     

钨合金复烧工艺及机理研究

提高烧结态钨合金强度及延伸率的热处理方法到目前为止比较成熟并且在大批生产实际中应用的只有真空热处理。本文介绍了在分解氨气氛中选择适当的工艺参数对烧结态钨合金进行热处理,同样可以明显改善钨合金的强度和延伸率,并对其机制进行了探索。     

不同弹芯材料侵彻钢装甲对靶板硬度的影响

对钨丝增强非晶复合材料和93钨合金进行模拟靶试对比试验,通过对弹坑头部附近靶板进行微观组织观察和显微硬度测试,研究高速侵彻后不同弹芯材料对靶板组织和性能的影响。结果表明:两种弹芯材料高速侵彻后的钢靶板,弹坑附近的靶板硬度都较侵彻前的原始靶板有很大提高,且非晶复合材料弹芯侵彻形成的弹坑附近高硬度层更宽,其宽度是93钨合金弹芯侵彻形成的高硬度层的2.5倍左右;弹坑附近组织存在很大差异,钨合金弹芯的弹坑附近是形变织构组织,而复合材料弹芯靠近弹坑处的靶板发生了马氏体转变。     

两种钨合金材料力学行为及微观损伤研究

首先测试83W旋锻(8Fe-9Ni-83W)和89W径锻(5Fe-6Ni-89W)两种钨合金棒材的各向异性情况,然后对两种钨合金材料分别进行了温度从-196℃到800℃的动、静态压缩试验(应变率10-3~7 000 s-1)和拉伸试验(应变率10-3~1 000 s-1),得到了其应力应变关系曲线和失效应变。结果表明:两种棒材都存在各向异性特性,钨合金棒材沿径向硬度不均匀,越靠近棒心,硬度越低。随着应变率的升高和温度的降低,两种钨合金材料的流动应力升高;在所研究的温度范围内,一定应变率下两种钨合金材料都出现了动态应变时效现象;两种钨合金材料的失效应变随着应变率的增大而降低。最后观察钨合金试验后的金相照片,给出应变率和温度以及钨颗粒含量对其损伤模式的影响。     

液相烧结钨合金的氧富集脆化机理及韧化工艺的研究

用扫描俄歇探针（ＳＡＭ）结合真空热处理试验，研究了９５Ｗ-Ｎｉ-Ｆｅ合金的脆化 机理，发现烧结态合金中散布着氧的高浓度富集区，这是钨合金脆化的重要因素。１０００℃以 上的真空热处理可以消除氧高浓度富集区和降低界面氧浓度，使合金延性、韧性显著提高。     

高比重钨合金的静液挤压强化

对高比重钨合金经静液挤压变形强化后的力学性能、微观组织及断口形貌进行了分析和研究 ,并对静液挤压这种加工工艺对钨合金材料的变形强化机理进行了初步探讨。     

高密度钨合金静液挤压组织和缺陷分析

采用新的变形工艺——静液挤压技术形变强化高密度钨合金材料,并进行了消除应力退火处理。实验表明:材料挤压强化主要是形成位错密度很高的胞状结构。材料形变后钨颗粒排列具有方向性,材料破断主要以钨颗粒解理断裂为主。挤压时材料缺陷是纵向裂纹、圆周裂纹及分层。     

93钨合金材料的模量、比热及热膨胀系数的温度效应

针对长杆穿甲弹在使用过程中可能经受的高低温环境 ,系统测量了弹芯材料 93钨合金在两种热处理状态 (真空退火状、旋锻态 )下的杨氏模量 E、剪切模量 G在 - 50～ 1 0 0 0℃ ,比热 Cp在 0～ 1 0 0 0℃及热膨胀系数 α在 2 1～ 90 0℃温度范围内的变化规律 ,并采用优化方法拟合得到了上述各参数和温度间的函数关系。在实验结果的基础上 ,通过间接计算得到了泊松比μ ,声速 C0 等参数值。本研究可为长杆穿甲弹的设计及研制提供必要的基础数据及规律     

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.     

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.     

Influence of Installing Error on the Surface Shape Precision of the Axial Symmetry Aspheric Workpiece in Lapping

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.     

Experimental Research on Output Performances of Giant Magnetostrictive Actuator

The paper introduces the performances of magnetostrictive actuators and its applications, discusses the design methods for the structure and internal magnetic circuit of a giant magnetostrictive actuator, and makes tests on the output displacement and force characteristics for an actuator using homemade magnetostrictive material. The experimental result shows that the actuator has satisfactory output precisions and ranges in transient and stable states, and can be used in lowfrequency vibration control system of precise equipment.     

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.