超声波金属焊接信号采集与分析系统

为了对超声波金属焊接过程进行分析并提取反应焊接质量的特征值,设计了一种基于LabVIEW的数据采集系统,主要包括传感器、信号调理电路、数据采集卡、系统主程序等四部分.本系统实现了对超声波金属焊接过程参数的采集、显示、存储和分析.采用小波分析的方法对电流信号进行分解,探索电流信号与焊接质量相关联的特征.超声波金属焊接试验结果表明,采集系统能够对多路信号进行同步准确的采集和初步分析;电流信号基频频率段信号的幅值,变化趋势在一定程度上反应焊接质量,电流信号基频频率段信号有效平均值过小或者变化趋势不明显都将导致焊接失效.     

基于虚拟仪器的多信息融合电阻点焊质量检测系统研究

采用虚拟仪器技术和多信息融合技术建立了对铝合金点焊质量的检测系统。系统应用分形理论对焊接过程中采集的数据信息进行了处理,使用虚拟仪器工具编程提取了更能反映所采集信号统计特征和变化特征的盒维数。在对焊点质量与焊接过程中信息的盒维数统计物理关系的分析基础上建立了基于模糊控制理论的焊点质量判定系统。仿真实验结果表明,本系统能够准确地判定电阻点焊的焊点质量。与传统的电阻点焊质量检测系统相比,具有更加准确、快速和成本低廉的优点。     

多源信息驱动的焊接典型缺陷在线智能识别

为避免转向架的焊接过程出现烧穿、未熔合、卡丝、夹渣等缺陷,文中构建了转向架机器人MAG焊接过程信息采集系统,能够实时采集熔池图像、电弧声音及电压信息.分别提取了与质量密切相关的关键特征,并基于XGBoost模型开展了知识建模与融合分析.最终实现了类似于焊接技能大师的信息感知与质量分析能力,综合精度可达90％以上,从而提升了转向架焊接作业的质量可靠性与智能制造水平.     

基于空间电荷采集实现电子束焊接过程实时监控的装置及方法

为了实现电子束焊接过程的在线监控,保证焊缝成形质量,研制了一套空间电荷信号采集处理系统,系统由传感采集模块、信号处理模块和显示分析模块组成.通过多组6061铝合金平板对接焊接工艺试验,实时采集焊缝熔池正上方8个位置的电荷,分析电荷信号波形特征与焊接成形质量关系规律,建立了波形变化对焊缝成形质量判据准则.结果表明,该系统采集的信号波形能够有效的评价焊接过程稳定性,以及实时判断焊偏、未熔合、焊穿等成形缺陷.     

基于点焊监测波形的焊接质量在线判定

利用传感技术形成电阻点焊信息采集系统,采集点焊过程质量信息,包括焊接电流、焊接电压、动态电阻和电极位移等。实时输出各参数波形,并依据波形变化特征对焊接质量进行在线判定,同时分析焊接热量变化对焊接质量的影响,从而定量分析焊件熔核尺寸、压痕深度、是否飞溅等质量信息,并可对焊核的焊接强度做出定性判定。     

副车架侧梁多机器人焊接工作站设计与仿真

针对目前对于副车架的生产制造的研究较多的是对其前期结构设计和优化,而对其自动化生产的研究较少的情况,通过分析其焊接过程,设计一种由两台焊接机器人和两台搬运机器人组成的自动化焊接工作站。在机器人仿真软件RobotStudio中根据机器人焊接工作站布局建立仿真环境,在仿真系统中创建Smart组件并设计组件内部信号连接以实现动画过程,为4台机器人导入各自的机器人系统,并为各系统创建I/O信号,通过工作站逻辑将各系统间信号进行连接实现各系统间通信。最后按遗传算法规划的最优焊接路径,利用仿真软件自动编程。仿真过程表明了所建工作站布局的正确性,为汽车副车架侧梁的自动化焊接和类似的仿真设计提供了指导。     

多元化铝合金直流点焊质量监测系统的研发

为了克服由于多种电阻点焊质量影响因素引起的单参数检测技术的不足,充分利用点焊过程中各种参数所提供的熔核质量信息,工作中构建了以焊接磁场、焊接电压、电极位移,作为铝合金点焊质量评定特征信息的铝合金点焊质量监测系统。试验证明,监测系统能够高速准确地采集铝合金点焊过程的多个特征信号,并能有效反映点焊过程中焊点熔核的变化,对焊点质量作出准确判断,满足点焊过程质量监测的要求。     

多元化铝合金直流点焊接质量监测系统的研发

为了克服由于多种电阻点焊质量影响因素引起的单参数检测技术的不足,充分利用点焊过程中各种参数所提供的熔核质量信息,工作中构建了以焊接磁场、焊接电压、电极位移,作为铝合金点焊质量评定住处特征信息的铝合金点焊质量监测系统.试验证明,监测系统能够高速准确地采集铝合金点焊过程的多个特征信号,并能有效反映点焊过程中焊点熔核的变化,对焊点质量作出准确判断,满足点焊过程质量监测的要求.     

基于点焊U-I图的信号采集与喷溅分析

基于Windows环境、高速数据采集卡PCL1800和工控机通用平台,采用VC++开发了一套信号采集、信号处理、实时显示的焊接电信号测试分析软件。该系统能精确采集点焊过程的电极间电压和焊接电流波形,并提取出焊接过程动特性的喷溅特征信息,从而为高性能焊机的研制和焊接参数的优化提供了一个强有力的工具。     

T形接头机器人GO2焊接过程实时监控

针对T形接头的机器人CO2焊接,建立了焊接过程的实时监控系统,对电弧传感器采集的焊接电参数信息实施在线处理与特征提取.构建焊接电流瞬时值标准差、峰度和变异系数的三维特征矢量,描述正常焊接过程与受到干扰的焊接过程之间的区别.将三维特征矢量作为模糊Kohonen聚类神经网络系统的输入,对焊接过程进行识别,为实时监控机器人CO2焊接过程奠定了基础.     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.     

INTRODUCTION TO PATENTS

The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.     

China Foundry Week 2014

China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society （FICMES） each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.     

17th Conference of Hydrodynamic and Electromechanical Control Engineering Call for papers

正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.     

Information for Contributors

正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis     

Preface

<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of     

Information for Contributors

The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.     

Formulas of Tension of Continuous Rolling Process

The development of computer controlled continuous rolling process calls for a mathematical expression that can express the inequality condition of "constant flow". Tension is the link of the continuous rolling process. From the condition of dynamic equilibrium, a differential equation of tension is given out. On the basis of the physical rules established from the industrial practice and experimental studies, the law of volume constancy, the linear relation of forward slip and tension, the state equation of continuous rolling, the formula of dynamic tension, and the formula of static tension have been obtained. These formulae reflect the functional relations between tensions, thickness, roll velocity, and time in the continuous rolling process. It is implied that the continuous rolling process is a gradually steady, controllable, and measurable dynamic system. An assumption of predicting the thickness of a steel plate using these tension formulae is also put forward.