液压剪切机的（PC）自动控制

本文介绍了可编程序控制器（PC）在液压剪切机加工过程自动控制中的应用。文中讲述了剪切机的工作原理及PC控制的硬件结构与程序设计。液压剪切机由PC控制，简化了电气线路，增强了控制的柔性，并具有工作可靠、维护方便、易于扩展功能的特点。     

PLC在气动控制电极板剪切机中的应用

本文详细阐述了气动控制系统、光电检测、可编程控制器在气动电极剪切机中的应用。     

从“第七届欧洲国际机床展览会”看机床制造业的发展

文章透过7·EMO展品,分析了机床制造业及机床工具产品的技术发展趋势。作者认为:机床的数控化,多功能化,可编程序控制器在机床上进一步普及,新材料的推广,进一步提高机床的生产率、精度,追求外观造型以及强化社会分工生产是机床产品及制造业的主要发展趋势.     

模糊神经网络在数控全闭环系统位置控制上的应用

在数控全闭环系统中,采用带摩擦补偿与积分环节的模糊神经网络复合控制器作为位置控制器,搭建数控全闭环系统仿真模型,对比单纯P调节器、模糊控制器及模糊神经网络控制器的仿真控制效果。结果表明:使用复合控制器的全闭环系统具有良好的动、静态特性,性能优于上述其他控制器。     

液压多功能剪切机

液压多功能剪切机在结构上采用了中压液压传动、双柱塞复合油缸,新型机械武换向装置和新型销轴传递扭矩联轴器,使整机结构紧凑、体积小、造价低、噪音小、操作灵活、安全可靠、搬运方便、重量轻并易于实现过载保护,效果显著。     

基于PLC的经济型龙门式数控钻床控制系统设计

以可编程控制器为核心,采用上位机、伺服控制器、传感器和液压技术,设计了经济型数控钻床控制系统,使数控钻床具备了精确定位、自动钻孔的功能。     

基于内模控制的数控转塔冲床单冲控制器设计与仿真

针对数控转塔冲床被控对象的纯滞后特性,设计一种基于内模控制的数控转塔冲床单冲系统控制器。仿真结果表明:与传统PID控制器相比,内模PID控制器参数整定简单,具有良好的抗干扰性、稳定性和鲁棒性。     

Trumatic180—型带激光头的冲剪机

利用激光射线可以迅速、精密地切割几乎全部金属板材并且噪声极小。因此,特龙夫(Trumpf)公司把板料的激光切割和该公司的Trumatic型数控冲型剪切机的传统工艺,使冲孔、冲形剪切和成形,综合在一台Trumatic—180型激光冲剪机上(图1)。     

基于ABAQUS的剪切机箱体仿真分析及优化设计

剪切机箱体是剪切过程中主要的承力部件,其结构的强度和刚度决定了整个设备在工程运用中的可靠性和安全性。基于ABAQUS软件,对剪切机建立了有限元分析模型。通过设计载荷试验,对比了剪切机箱体变形的试验值和分析值,验证了有限元分析模型的正确性。针对剪切机箱体应力和变形较大的问题,对剪切机箱体进行优化设计,并对优化设计后的剪切机箱体再次进行了有限元仿真分析。优化后的剪切机箱体应力和变形得到了明显改善,为剪切机箱体的结构设计和优化提供了参考。     

基于ADAMS的摆式剪切机的运动仿真分析

以上下剪刃同时运动剪切轧件的摆式剪切机为研究对象,对其平面机构进行分析,并在CAD系列软件SolidWorks中建立摆式剪切机剪切机构的三维模型,与虚拟样机仿真软件ADAMS相结合,对导入ADAMS中的模型进行运动仿真以分析其动态性能。从仿真结果可以了解摆式剪切机的剪切状况,反应剪切过程中出现的问题,同时验证所设置的驱动条件下剪切机良好的剪切性能,为摆式剪切机的研究提供了依据。     

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.