TiB2-40Ni金属陶瓷粉末与涂层组织结构的研究

采用机械合金化技术制备TiB2-40Ni金属陶瓷复合粉末,通过超音速火焰喷涂技术制备TiB2-40Ni金属陶瓷涂层,研究TiB2-40Ni粉末在不同球磨时间下的显微组织和物相,研究TiB2-40Ni涂层的组织结构、孔隙率和硬度。结果表明:随着球磨时间的延长,逐渐细化的陶瓷相TiB2包覆在Ni表面的含量增加;与粉末的主要物相相同,TiB2-40Ni涂层为TiB2和Ni相,涂层组织较致密,孔隙率低,平均硬度值为(643.5±56.8)HV0.3。     

TiB2增强50Ni基金属陶瓷复合粉末与涂层的研究

采用机械合金化技术制备球磨TiB2-50Ni金属陶瓷复合粉末,通过超音速火焰喷涂技术制备TiB2-50Ni涂层,研究不同球磨时间得到TiB2-50Ni粉末的显微组织和物相,研究TiB2-50Ni涂层的显微组织、物相结构、孔隙率和硬度。结果表明,随着球磨时间的延长,陶瓷相TiB2逐渐破碎,黏结相Ni变形严重,且TiB2包覆在Ni表面的含量增加;粉末与涂层的主要物相为TiB2和Ni相,涂层组织致密,孔隙率低,平均硬度值为（597.9±36.1）HV0.3。     

TiB2增强50Ni基金属陶瓷复合粉末与涂层的研究

采用机械合金化技术制备球磨TiB2-50Ni金属陶瓷复合粉末,通过超音速火焰喷涂技术制备TiB2-50Ni涂层,研究不同球磨时间得到TiB2-50Ni粉末的显微组织和物相,研究TiB2-50Ni涂层的显微组织、物相结构、孔隙率和硬度。结果表明,随着球磨时间的延长,陶瓷相TiB2逐渐破碎,黏结相Ni变形严重,且TiB2包覆在Ni表面的含量增加;粉末与涂层的主要物相为TiB2和Ni相,涂层组织致密,孔隙率低,平均硬度值为(597.9±36.1)HV0.3。     

TiB2增强Co基金属陶瓷粉末与涂层组织结构研究

采用机械球磨方式TiB2增强Co基金属陶瓷复合粉末,通过超音速火焰喷涂技术在Q235钢基体表面沉积TiB2-40Co金属陶瓷涂层,研究不同球磨时间粉末颗粒的组织结构,利用XRD分析粉末与涂层的物相,研究TiB2-40Co金属陶瓷涂层组织结构。结果表明:TiB2陶瓷硬质相与Co黏结相之间结合良好,且随着球磨时间的延长,Co黏结相塑变明显;涂层组织致密,涂层的主要物相与粉末相同,主要为TiB2和Co两相;经120 h熔融铝硅腐蚀后,TiB2-40Co涂层具有良好的抗熔融铝硅腐蚀性能。     

冷喷多尺度WC-Co金属陶瓷涂层结构与性能研究

以团聚烧结工艺制备的多尺度WC鄄12Co、WC鄄10Co鄄4Cr 和WC鄄17Co 粉末为原料,利用冷喷涂沉积多尺度WC鄄Co 金属陶瓷涂层,研究了涂层的组织和相结构,测定了涂层的显微硬度、弹性模量和断裂韧性,并通过销鄄盘磨损实验测定了涂层的耐磨损性能。结果表明:3 种冷喷多尺度WC鄄Co 金属陶瓷涂层组织均比较致密,涂层保持与原始粉末相同的相结构,粘结相Co 由于强烈塑性变形发生了部分同素异构转变,涂层组织无传统层状结构,WC 颗粒呈现微米、亚微米及纳米多尺度分布特征;随着喷涂粉末中粘结相含量的增加,涂层硬度和弹性模量降低、断裂韧性增加,其磨损失重有所增加;涂层磨损失效机理主要为磨粒对涂层的切削作用。     

铝合金表面耐磨涂层的制备研究

采用气雾化工艺研究制备Fe Ni Cr BSi合金粉末,并通过HVOF工艺在铝合金表面制备耐磨涂层,涂层最大厚度可达3.0 mm。用金相显微镜、激光粒度仪以及维氏显微硬度仪等分析粉末颗粒的形貌、粒度分布、显微硬度以及涂层的表面形貌、内部组织和显微硬度。结果表明:不同雾化工艺对合金粉末的粒度分布影响较大,当雾化温度及压力分别为1 500℃、3.5 MPa时,所制得的粉末平均粒径为13.3μm,且粒度分布合理,颗粒表面光滑、形状规则,采用该粉末制备的HVOF耐磨涂层孔隙率为1.23%,内部组织以针状马氏体为主,硬度高达635HV0.3。     

超音速等离子喷涂Cr2O3陶瓷涂层的微观组织及其耐磨性能

采用超音速等离子喷涂技术在纯铜基体上制备Cr2O3-Ni-5%A(l质量分数)陶瓷涂层。利用XRD、SEM、激光共聚焦显微镜(LSCM)、显微硬度仪对涂层进行表征与分析,通过Image-pro Plus图形软件计算涂层的孔隙率,并通过摩擦磨损试验评价涂层的耐磨性能。结果表明:除了喷涂过程中出现了少量铬的氧化外,起始粉末和涂层的物相没有发生变化;陶瓷涂层表面呈双态组织,其表面粗糙度(Ra)为4.763μm;涂层断口形貌为典型的片层状组织,在涂层的抛光截面上可见紧密的富铬带均匀分布;Cr2O3涂层的孔隙率为1.2%,显微硬度为1 640HV0.3;涂层在室温下的摩擦因数约为0.4,其磨损机制为磨粒磨损。     

镁合金表面冷喷涂420不锈钢涂层及其摩擦磨损性能研究

采用冷喷涂技术在AZ80镁合金表面制备420不锈钢耐磨涂层,开展喷涂工艺参数和涂层组织结构研究,并初步比较耐磨涂层与38Cr Si钢的摩擦学性能。结果表明:随着喷枪移动速度的下降,涂层的孔隙率逐渐下降;涂层形成过程中,420不锈钢粉末中的奥氏体相发生应变诱导马氏体相变,在一定程度上提高了涂层硬度;涂层在摩擦过程中的摩擦磨损机制表现为磨粒磨损和黏着磨损;涂层的耐磨性能显著优于38Cr Si钢。     

有氧烧结Ni60/WC合金涂层的组织和性能

在有氧烧结条件下,在45钢基体上制备Ni60/WC自熔合金涂层。利用XRD、SEM、EDS等对涂层的组织和性能进行分析。结果表明:涂层中主要有γ-(Ni,Fe)、WC、(Cr,Ni)23C6、Co3W3C、Ni2B等相组成,涂层平均显微硬度为918.4HV0.1;在磨粒磨损条件下,磨损率为1.47×10-2 cm3/h;过渡层的显微硬度从918.4HV0.1至220HV0.1呈梯度分布,宽度约为0.30mm。     

数控机床刀具的石墨烯复合涂层性能研究

采用机械球磨后激光熔敷方法,在WC-6%Co数控机床刀具表面制备石墨烯-Cr Al Ni复合涂层,并进行物相组成、显微组织分析,以及与Cr Al Ni常规涂层的耐磨损性能和抗氧化性能对比。结果表明,复合涂层由石墨烯、Ni Al相和Cr组成,显著改善数控机床刀具的耐磨损性能和抗氧化性能。与Cr Al Ni常规涂层相比,石墨烯-Cr Al Ni复合涂层25℃磨损体积减小66%、250℃磨损体积减小72%、500℃磨损体积减小74%,900℃高温氧化60 min后质量增加率减小91%。     

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.     

Method for Measuring Velocity of Warhead Fragments Based on Photoelectric Detection

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.     

数码电子雷管中影响点火头性能因素分析

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。     

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.