20MN大型框架式液压机机身有限元分析及优化设计

针对20 MN大型数控框架式液压机机身CAD分析及优化,应用三维软件Solidworks建立了20 MN大型数控框架式液压机机身的三维模型,采用有限元分析模拟软件ANSYS建立了有限元计算模型,并进行静态刚强度分析.计算分析了机身的应力及应变,在此基础上构建了主体结构的优化计算模型,将机身进行了优化设计,并与初始设计进...     

基于ANSYS的环锻液压机结构优化分析

本文介绍了利用建模软件SolidWorks,设计模拟了环锻液压机机身结构,并利用有限元分析软件ANSYS对机身机构进行了受力仿真分析计算,得到了机身在满吨位压力下的应力和变形云图,通过结合材料性能,结合此类型液压机设计规范,对机身结构的高低应力和变形情况进行了结构优化分析。为该类环锻液压机的快速设计提供了理论支撑和可靠数据支持。     

5000kN双梁式复合材料液压机结构设计与有限元仿真

为解决复合材料三梁四柱液压机结构轻量化与成形工艺零件厚度不均匀问题,设计一台5000kN新型双梁双抗偏载结构的液压机。使用SolidWorks建立机身初始结构模型,采用ANSYS Workbench对液压机模型进行静态有限元分析,得到机身主要部件的应力和位移的分布情况,确保机架的刚度和强度以及整体性指标达到使用要求。同时,在中心载荷和两种极限偏载工况下,对液压机结构进行强度和刚度校核,获得满足工程要求的新型双梁液压机结构。     

闭式单点高速压力机机身的有限元分析

运用三维设计软件Solidworks 2016建立了闭式单点高速压力机机身的3D模型,并根据其结构特点,利用有限元分析软件ANSYS Workbench15.0对其进行静力学分析和模态分析,得到机身的总变形云图、有效应力云图、机身前六阶固有频率及相应的振型图,并对模拟结果进行分析,为机身结构的优化设计提供必要的理论参考。     

模锻压力机机身结构与刚度分析

针对模锻压力机整体机身结构,通过三维建模软件建立1600t模锻压力机机身分析模型,并导入ANSYS有限元计算软件进行仿真分析。对机身及拉紧螺杆的几种状态进行分析计算和对比,获得了最为合理的结构形式。     

基于有限元的大吨位压力机立柱结构改进

通过有限元理论研究方法,针对1300t多连杆压力机采用全接触立柱和悬置立柱两种不同结构进行有限元分析.建立两种不同形式的机身三维模型,采用有限元分析软件ANSYS建立计算模型,并进行工作情况和预紧力情况下的静力学分析对比,验证采用悬置结构的可行性和安全性,并对立柱进行优化设计.设计结果为立柱悬置结构设计提供了理论依据.     

机械粉末成型压机的强度刚度计算与分析

运用SolidWorks软件对500t机械粉末成型压机主机及模架进行了实体建模,并运用ANSYS有限元分析软件对其进行了结构强度分析;通过分析获得机身和模架各模板应力和应变的分布情况,计算出相应的挠度刚度,在此基础上分析了机械粉末成型压机的机身和模架结构设计的是否合理,并做了相应改进。     

数控转塔冲床机身模态分析与优化设计

采用有限元分析软件ANSYS对数控转塔冲床机身进行有限元模拟,并与实验相结合,对其进行模态分析和优化设计,得到机身的最优结构模型.由分析可知,改进后的机身动态性能得到了极大提高.     

冷锻压力机机身振动特性的模态研究

为更加合理地设计冷锻压力机的机身,使机身抗振、安全、可靠。以北京机电研究所CWFP式12500 kN冷锻压力机为例,首先使用ABAQUS有限元分析软件计算其机身的固有频率,提出几种改进方案,分别进行有限元分析,与原机身的分析结果进行对比,并采用SolidWorks软件画出机身的三维模型。然后再次使用ABAQUS软件对改进方案进行分析,对其影响因素进行了验证与分析。经验证发现,在机身关键部位加筋是影响机身固有频率最重要的因素。     

基于OptiStruct的闭式压力机组合机身的拓扑优化

通过拓扑优化寻找机身材料的合理布置,以闭式压力机组合机身为研究对象,利用SolidWorks建立机身的三维模型,然后导入到HyperMesh中,建立有限元分析模型。采用变密度法,以静力学分析为基础,定义材料的密度为设计变量,设置不同的约束条件和目标函数,通过Opti Struct求解器对机身进行拓扑优化。通过对比两种方案的优化结果,改进机身的结构,并对优化后的模型进行静力学和模态分析,验证了优化后的压力机机身符合实际使用要求。优化后压力机机身重量减少7.6%,实现了机身的轻量化,节约了成本,提高了企业的竞争力。     

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.     

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。     

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).     

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.     

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.     

The Mirror with Patterns of Auspicious Animals and Grapes——Exquisite cast mirror and the technology of surface tin-enrichment by rubbing-in and infiltration of tin-rich powder

<正>Bronze mirrors were used by the Chinese people before the introduction of the glass mirror.Only after it was replaced by the glass mirror did the bronze mirror gradually retreat from people's lives.Different styles of bronze mirrors were made in different historical periods,particularly in the Warring States Period,the Han and Tang Dynasties,which were the three peaks of the development of bronze mirror arts in ancient China.The casting techniques were exquisite.The surface of the bronze mirror was smooth and bright enough to reflect one's image,and there were scarcely any casting defects on the mirror surface.On the back of the bronze mirror,there were rich depictions of Arts and Humanities,and the ornamentations were also     

The 9th China International Diecasting Congress & Exhibition

The 9th China International Diecasting Congress ＆ Exhibition was held on July 22-24, 2014 at Shanghai New International Expc Centre. This exhibition was the most successful over the years, with over 6890 visitors and 155 exhibitors, and the exhibition area increased by 30% from 9,500 square meters in 2012 to 12340 square meters. Die casting enterprises from a total of 24 countries and regions, including China mainland, Chinese Taiwan and Hong Kong, South Korea, Japan, Germany, India, Thailand, Malaysia, the United States, Russia, Australia, Iran, Ukraine, Brazil, Colombia, Singapore, Austria, Canada, Croatia, France, Turkey, United Kingdom, Vietnam, attended the congress and exhibition.     

Introduction of the Fluid Control Engineering Institute of Kunming University of Science and Technology

正The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining produc-     

RARE METALS Volume Contents

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