点杂多晶太阳能硅片电解磨削多线切割试验研究

提出了一种电解磨削多线切割点杂多晶太阳能硅片的新方法。电源的正极接硅锭,负极接切割线网,电解过程中硅锭发生微区钝化反应,形成硬度较小的钝化膜,使点杂多晶太阳能硅片更易切割。试验结果表明:该技术具有切割效率高、切片合格率高等优点。进一步检测发现,硅片宏观表面线痕浅、隐裂少,微观表面平整性好。该技术的应用降低了硅片加工的成本,提高了硅材料的利用率,也为太阳能电池的运用拓宽了空间。     

基于数控机床远程监控技术的安全传输系统开发

为了保证数控机床远程监控系统数据传输的安全性,文章在Linux及windows系统下,基于C/S层次结构,采用TCP/IP网络协议,利用C/C++语言、VS2008开发软件、oracle数据库,开发了基于非圆磨削数控机床远程监控系统的安全传输系统,该系统实现了各监控机床站点的身份认证,密钥协商、密钥校验、密钥周期更换,以及业务数据录入数据库和对传输数据的加解密等功能,具有不依附于平台、加密实时性高、易用性好和维护性强等优点。最后将系统部署到西门子840Dsl实验台和远程监控PC端进行实验验证,实验结果表明软件运行稳定,达到了预期的目的。     

基于LabVIEW的磨加工状态监控系统双线程技术研究

为开发实时性好、精度高的磨削加工状态监控系统,提出了利用磨削加工中的声发射技术实现磨削加工状态监控的方案。采用LabVIEW软件,在开发基于AE的磨削加工状态监控程序各个模块的基础上,分别利用局部变量法和生产者/消费者模式的两种双线程方式设计总体程序结构。最后通过实验对两种双线程方式的实时性、精确性优劣进行了比较。实验结果表明,采用生产者/消费者模式的磨加工状态监控系统双线程程序的实时性更高,精确性更好。     

焊接机器人数据采集与管控系统

随着数字化焊接机器人进入工厂,采用传统人工监督的方式逐渐不能满足对设备的监控管理需求。一些采用“多机器人厂商、中小生产规模”为生产模式的企业,需要一个低成本、高适配性的平台,统一管理现场各种焊接机器人。针对上述需求设计了机器人管控系统,系统可分为通信模块和设备管控模块。其中,通信模块采用C/S架构开发,通过Netty框架搭建NIO服务器接收实时数据,开发的基础通信框架能够适配多种通信协议,接入不同品牌的机器人;设备管控模块采用B/S架构开发,基于Spring MVC框架实现,通过统一的平台对各个品牌机器人进行管理、监控和维护,以及历史数据的展示等。经现场运行验证,该系统能实现不同品牌机器人的统一监管,并且能够长时间稳定运行。创新点：(1)数据通信模块通过基础通信框架的开发,能够适配多种通信协议,并且支持通信程序远程更新。(2)机器人管控系统平台能够快速接入各种机器人,实现不同品牌的机器人统一化的监控、维护和管理。     

太阳能硅片切割技术的研究

简述了太阳能硅片常用的切割方法及特点,指出电火花线切割由于其适合大厚度、超薄切割等特点,将成为太阳能硅片切割的一个研究热点.但因半导体特殊的电特性,目前常规电火花线切割工艺还不能胜任太阳能硅的切割.研究了太阳能硅材料的放电加工模型,提出了电火花线切割太阳能硅片的思路和工艺方法,并采用改进的脉冲电源首次对电阻率为2.1 Ω*cm的P型太阳能硅进行了切割试验,切割效率大于100 mm2/min.     

金刚石线锯电解磨削切割多晶硅片的试验研究

基于金刚石线锯切割系统,开展了金刚线电解磨削切割多晶硅片试验。结果表明:电解磨削复合加工方法在机械磨削的同时复合了阳极氧化和腐蚀,在硅片表面产生了机械损伤缺陷和电化学腐蚀缺陷。酸制绒时腐蚀反应在两种类型缺陷处顺利进行,形成均匀致密的绒面结构,有效降低硅片表面反射率,有利于后续电池片光电转换效率的提高。     

一种基于物联网的电火花线切割机床远程监控管理授权系统

为了解决往复走丝电火花线切割机床长时间工作时需操作人员在附近值守的问题,通过对单片机和ECS云服务器的研究与运用,基于工控计算机控制的电火花线切割机床,开发了一款远程监控管理授权系统,并对新系统未来的发展和应用提出了几点思考。该系统与移动终端APP互联,具有远程报警、远程监控和远程授权功能,其目的是减轻操作人员的劳动强度和提高加工过程的实时控制能力。     

基于小样本数据驱动模型的硅片线切割质量预测

在单晶硅加工中,硅片多线切割质量检测耗时和检测成本高造成硅片质量检测难。因此,提出一种基于生成对抗网络(WGAN-GP)数据处理与自注意力残差网络(SeResNet)的硅片质量预测方法。分析多线切割的机制,确定影响硅片质量的工艺参数,建立数据样本,使用WGAN-GP对样本数据进行数据增强。在此基础上,建立基于SeResNet的硅片总体厚度偏差预测模型。以硅片的多线切割加工过程监控数据为模型验证数据,对构建的硅片总体厚度偏差预测模型进行验证。实验结果表明：该模型具有良好泛化性和高准确率,有效解决了小样本数据下的预测难题,实现了平均相对误差小于10%的硅片总体厚度偏差预测,所以基于数据驱动的硅片质量预测来代替硅片加工中的质量检测具有重要的现实意义。     

基于C#NET技术的巡检机器人远程监控系统的研究

针对传统监控系统缺乏对机器人的实时监控,无法实现对各类信号、视频数据的统一管理问题,基于C#.NET框架,使用C#语言,结合SQL Server2008数据库技术,以局域网为网络平台,TCP/IP为网络协议,开发一套巡检机器人远程监控系统。采用模块化设计思想,把系统分为精确定位、传感器状态显示、位姿状态显示、电量显示、自动与手动控制、数据库管理、视频监控等模块,介绍了各模块的设计及其实现过程。实际测试表明:该系统实时性强,稳定性好,具备良好的人机交互功能,满足巡检机器人远程监控系统的功能需求。     

小型制造单元远程可视化系统设计

为解决制造型企业生产设备数据采集、可视化、远程监控及管理等问题,设计基于B/S架构的生产企业小型制造单元的远程可视化系统。通过对企业生产过程中数据采集及远程可视化问题进行深层次的分析,设计远程可视化监控系统的通信总体技术框架。利用OPC、SQL技术,实现基于B/S架构的小型制造单元远程可视化系统。系统由设备状态、仓储管理、运行监控等功能模块组成,通过图表直观地反映制造单元的设备、仓储、生产情况,通过可视化系统提高了企业生产过程中的管理水平。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

Thermodynamics Study on the Decomposition of Chromite with KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

Influence of Heat Treatment on Damping Behaviour of the Magnesium Wrought Alloy AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.     

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid(Pb)/liquid(Sn) diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field(B0.3 T). When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level(0.8–5 T), the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.     

Growth Kinetics of Single Inclusion Particle in Molten Melts

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.