Platinum-polyaniline-modified carbon fiber electrode for the electrooxidation of methanol

Platinum was electrodeposited onto a polyaniline-modified carbon fiber electrode by the cyclic voltammetric method in sulfuric acid, which may enable an increase in the level of platinum utilization currently achieved in electrocatalytic systems. This electrode preparation consists of a two-step procedure: fLrst electropolymerization of aniline onto carbon fiber and then electrodeposition of platinum. The catalytic activity of the platinum-polyaniline-modified carbon fiber electrode (Pt/PAni/C) was compared with that of a bare carbon fiber electrode (Pt/C) by the oxidation of methanol. The maximum oxidation current of methanol on Pt/PAni/C is 50.7 mA.cm^-2, which is 6.7 times higher than 7.6 mA.cm^-2 on the Pt/C.Scanning electron microscopy was used to investigate the dispersion of the platinum particles of about 0.4μm.     

相控阵超声检测技术在碳纤维结构分层缺陷检测中的试验

以碳纤维层压结构中容易产生的分层缺陷为研究对象,采用相控阵超声检测技术进行CIVA仿真和检测试验。通过声场及缺陷的建模和CIVA仿真检测试验,得出了碳纤维层压结构分层缺陷的理想检测参数。设计制作了模拟分层试验件,并进行实际检测试验,结果表明相控阵超声技术可以有效地检测该类缺陷。     

适合焊接应用的智能激光视觉传感技术

介绍了最新的激光视觉传感技术在汽车、造船、管道和铁路车辆等领域的自动化电弧焊接和激光焊接中的应用.先进且可靠的数字激光传感系统保证了电弧或激光热源能准确地对中准焊缝.在焊接过程中能够根据所测量的间隙和错边等数据实时地调整焊接过程参数,并在线检测焊后的焊缝成形和表面缺陷.从而保证焊接质量,并提高生产效率,降低总体焊接生产成本.应用这些适合焊接的智能化激光视觉传感技术.可以有效地提高焊接产品的质量和价格的竞争力.     

新型无芯碳纤维电热元件的失效分析及其制备工艺优化

对失效的碳纤维无芯电热元件进行综合分析,失效特征和显微结构分析结果表明,电热元件的高温定型以及脱芯工艺直接影响着其成品的寿命及电热特性.开发了适用于无芯碳纤维电热材料的高温热处理设备和新型的脱芯工艺.经测试,优化工艺之后的无芯电热元件的表面温度均匀性及工作寿命均有较大提高.     

The reinforcing mechanism of carbon fiber in composite adhesive for bonding carbon/carbon composites

A carbon fiber reinforced adhesive was developed for bonding carbon/carbon composites. The Weibull distribution method was used to analyze the bonding strength data, and the results showed that when the volume fraction of carbon fiber was 6 vol.%, the Weibull modulus was 42.9393 and the bonding strength of the adhesive was 11.3763 MPa. A model was proposed to explain the reinforcement of carbon fiber, and it was found that the strength of adhesive was a cubic function of the volume fraction of carbon fiber, and the function model was consistent with the Weibull data. We investigated that the carbon fiber could bridge adhesive matrix as a bridging effect for releasing the residual stress and inhibiting the extension of micro-crack.     

Flexible gripping technology for the automated handling of limp technical textiles in composites industry

A high level of cost-intensive manual tasks in the manufacturing process of composite parts impedes a further propagation of those innovative structures in important German industrial branches like the automotive sector or aviation. Especially the handling of semi-finished goods in several key process-chains could not be automated efficiently so far due to a great variety of materials and part contours as well as difficult handling properties of the limp, textile parts. Hence within the presented work a highly-flexible gripper system based on low-vacuum-suction is introduced, which is the result of a methodical investigation in the ideal gripping principle. Special actuators and an intelligent control strategy are combined into a selective gripping technology, which allows an automatic adaption of the pressure based holding force to different contours and materials, by closing certain apertures of a perforated plate. The experimental validation of a realized robotic end-effector shows that the challenging requirements of modern composite production could be fulfilled as the structural integrity of the technical textiles is preserved during the handling processes.     

能源工程焊接机器人的智能化技术

国民经济加速发展需要和综合国力支撑能力提升,使能源工程装备呈现出大型化、系统化和复杂化的显著特点,能源工程装备的工作地点也从陆地向太空、海洋和地下发展.在能源工程装备制造与安装过程中,焊接扮演着非常重要的作用,焊接金属结构件已成为产品制造发展的主要方向,金属结构制造基本实现了以焊代铸,向大型化、成套化、自动化方向的发展已成为时代的主流.新材料(种类和强度级别)不断涌现,因功能需要结构日趋复杂.各种焊接机器人不断涌现,焊接过程及焊接装备智能化特征凸显.智能化设备应有自主的决策能力,能够应付复杂的环境和条件变化.重点介绍无导轨磁吸附球面焊接机器人、复杂空间曲线焊接机器人、海底管道干式高压焊接修复机器人和海洋管道铺设焊接机器人的数字化与智能化.     

Electrode material for supercapacitors based on nanostructured carbon

Results are presented of studies of composite materials based on nanoporous carbon for application as an electrode material for supercapacitors with an aqueous KOH electrolyte solution. The optimum concentration ratio of the formula components for the electrode material is found on the basis of the studies of the power-capacitance characteristics of the studied samples of such capacitors.     

轧辊表面光纤激光毛化工艺研究

利用光纤激光柔性工作站对轧辊表面进行毛化,研究了激光射出头姿态、侧吹角对毛化点形貌、毛化后轧辊表面粗糙度的影响,分析了其影响规律,总结出最佳毛化工艺。结果表明,12点位置和3点位置在特定侧吹角度时,毛化点分布相对独立,凸台金属分布集中,无点与点搭接现象,毛化点形貌满足要求。12点位置和9点位置各侧吹角度下的毛化表面粗糙度均满足要求。综合对毛化点形貌和毛化后轧辊表面粗糙度要求,12点位置的毛化效果优于3点位置。研究结果已应用于实际生产。     

碳纤维鞋后跟成型模结构设计与研究

介绍了碳纤维塑料制品的应用及模具研发现状,分析了薄壁异形碳纤维鞋后跟的压制成型难点,阐述了模具设计与制造方案,通过整体式凹模配合组合式型芯、反向锥度推杆脱模等结构,保证了碳纤维鞋后跟的技术要求。研究结果对碳纤维塑料制品成型模的应用开发提供了较好的参考和借鉴。     

CIMS环境下的物流系统及搬运机构选择

介绍了ＣＩＭＳ环境下物流系统的组成，通过分析运储系统的任务和工作方式，介绍了物流系统中常用的搬运机械及其选择方法。     

长玻璃纤维增强聚丙烯复合材料拉伸试样纤维取向模拟研究

介绍采用Moldflow软件对长玻璃纤维增强聚丙烯复合材料拉伸件的纤维取向及拉伸性能进行模拟研究,对模拟后的纤维取向、拉伸模量、泊松比进行了分析,结果表明:沿流动方向,靠近浇口部位的平均纤维取向不佳,远离浇口部位的标距尾部和过渡部位的平均纤维取向较好,垂直流动方向上平均纤维取向存在分层;纤维取向整体呈现明显的皮芯结构;试样的拉伸模量和泊松比随纤维取向的变化呈现出与其相一致的趋势。     

微波烧结技术在超硬材料制品中的应用探讨

介绍了微波烧结技术的原理及特点,简要概括了目前制备特种陶瓷的研究现状,并对微波烧结陶瓷材料、硬质合金(WC-Co)、微波烧结金刚石烧结体等问题进行了分析讨论,初步探讨了微波烧结技术在超硬材料制品中广泛应用的可能性。     

Design and implementation of a precision material handling robot control system

Robotic transfer of silicon wafers in semiconductor fabrication facilities is becoming increasingly attractive. This paper discusses the benefits of a DSP-based computed torque controller over standard PID algorithms for a three degree of freedom, cleanroom material transfer manipulator. Formulation of robot kinematics, dynamic modeling, and numerical simulation assist in the implementation of this nonlinear controller. Simulation and experimental data correlate well and show that a factor of 2–3 times improvement in performance can be obtained.     

太阳能电动车碳纤维车身模具研制

阐述了将碳纤维应用于制作太阳能电动车车身可以大幅度减轻车身质量,从而降低能源损耗。详细介绍了设计制作1/5碳纤维车身模具的研制思路、制作过程以及已获得的经验和方法,从而为太阳能电动车碳纤维整车的研制提供了技术基础,并验证了全碳纤维车身的可行性。     

PAN基碳纤维长周期结构的温度依赖性

采用SAXS和HRTEM方法从倒易空间和实空间分别研究了PAN纤维碳化及石墨化过程中长周期结构及其变化。通过HRTEM测试发现碳纤维中存在由石墨微晶的有序堆砌结构,无序堆砌结构及过渡区形成的层状长周期结构,同时碳纤维的SAXS赤道方向散射曲线中出现肩峰,说明这种长周期结构沿纤维径向堆砌。通过SAXS研究发现,在PAN纤维碳化过程中长周期结构从700℃时开始出现且其尺寸随热处理温度的变化呈先增大后减小的趋势,转折温度区域约为1350℃左右。通过一维相关函数分析,计算了长周期结构中石墨微晶有序堆砌结构尺寸(Lo)、无序堆砌结构尺寸(Ld)、过渡区尺寸(Ltr)随热处理温度的变化:1350℃之前,Lo、Ld趋于增大,而Ltr趋于减小;1350℃之后3个参数均呈减小的趋势。     

碳纤维超薄笔记本外壳翘曲变形优化方案

利用Moldflow模流分析软件对碳纤维超薄笔记本外壳翘曲变形的影响因素进行模拟分析,针对影响塑件翘曲变形原因如冷却不均、分子取向和收缩不均等优化方案进行仿真验证,结果表明:优化冷却水路是改善笔记本外壳翘曲变形的最有效方法。     

汽车用钢铝异种材料的自冲铆接工艺智能优化

为了提高钢铝异种材料的铆接强度和平整度,提出了神经网络与启发式算法相结合的工艺优化方法.分析了自冲铆接工艺流程,确定了铆接接头质量参数和影响接头质量的工艺参数.设计了铆接实验,采用单隐藏层神经网络对质量参数与工艺参数间的非线性关系进行拟合.经过分析,拟合误差符合正态曲线分布,且误差均值接近于0,误差标准差极小,说明单隐...     

Densification mechanism of chemical vapor infiltration technology for carbon/carbon composites

Carbon/carbon composites were fabricated using pressure-gradient chemical vapor infiltration（CVI） technology with propane （C3H6） as the carbon precursor gas and nitrogen （N2） as the carrier gas. The chemical process of deposition of pyrolytic carbon was deduced by analyzing the component of molecules in gas phase and observing the microstructure of deposition carbon. The results show that the process of deposition starts from the breakdown of C-C single bond of propene （C3H6）, and forms two kinds of active groups in the heterogeneous gas phase reaction. Afterwards, these active groups form many stable bigger molecules and deposit on carbon fiber surface. At the same time, hydrogen atoms of the bigger molecules absorbed on carbon fiber surface are eliminated and the solid pyrolytic carbon matrix is formed in the heterogeneous reaction process.