采用激光焊的行李箱外板上段冲压工艺研究

行李箱外板上段与下段采用激光焊结构,对成形制件搭接边的表面质量及尺寸精度要求较高,由于翻边深度较深,翻边时产生坑包波浪且回弹严重,针对翻边后回弹及表面质量缺陷等问题,从制件结构及工艺设计两方面进行优化,提高成形制件尺寸精度及面品质量,缩短模具调试、整改周期,降低整车制造成本,提高市场竞争力。     

斜楔机构在汽车侧围外板翻边模中的应用

根据汽车侧围外板不同位置的翻边特点采用不同的斜楔机构成形,为解决侧翻边存在负角成形和取件问题,提出了3种新型斜楔机构,并介绍了侧围外板的冲压成形工艺和3种斜楔机构在侧围外板翻边模中的实际应用,可提高零件成形质量,降低模具开发成本。     

旋转斜楔机构在汽车侧围外板翻边模中的应用

分析了汽车侧围外板的冲压成形工艺,提出了一种新的斜楔机构———旋转斜楔机构。将双向运动斜楔与旋转斜楔进行了对比,在侧围板外覆盖件翻边模具中采用旋转斜楔成形机构,大大提高了生产效率。     

轿车侧围外板冲压成形工艺优化

通过分析轿车侧围外板结构特点及成形工艺过程,采用特殊的复合结构模具,通过修边与整形复合、直翻边整形与斜楔翻边复合及直翻边与斜楔冲孔复合,使轿车侧围外板冲压工序由5道减少至4道。经生产证明:优化后的冲压工艺可行,模具数量减少,缩短了模具生产周期,提高了生产效率,降低了制造成本,为类似冲压件的工艺设计提供了有益借鉴。     

汽车侧围外板侧翻边双驱动滑车斜楔机构设计

通过对汽车侧围外板结构及成形工艺进行分析,设计了一种双插刀滑车斜楔机构实现汽车侧围外板成形,该机构先后驱动不同方向的滑车,实现了零件负角翻边,并在零件完成冲压后从Z向垂直取件,解决了侧围外板成形过程中起皱与缺料现象,提高了零件成形质量,对同类零件的模具设计具有一定的参考作用。     

基于短工序化的侧围外板冲压工艺与模具设计

为了减少侧围外板冲压模具工序数量,降低新车型冲压模具投资,以某SUV车型侧围外板为例,通过对产品成形性和模具结构可实现性进行分析,设计了满足短工序化的冲压工艺方案。引入多种复合模具结构和特殊斜楔,实现了侧修边与侧冲孔、侧翻边与侧冲孔、侧整形与侧翻边等不同工艺内容的同序化,从而将侧围外板冲压模具工序数量由4道工序缩短至3道工序,并完成工业化应用。实践证明,短工序化工艺方案可有效削减模具工序数量,提高生产效率,降低模具开发及后期生产成本,满足侧围外板的批量生产需求,对于汽车行业冲压模具的工序优化具有一定借鉴意义。     

汽车前柱加强板冲压工艺及模具设计

以某汽车左前柱下部加强板为研究对象,根据其结构特征,设计了落料→拉伸成形→修边冲孔侧修边→翻边整形→冲孔侧冲孔修边5道工序成形,并运用Autoform有限元分析软件进行冲压成形数值模拟。依据工艺设计内容,运用UG、CATIA和AutoCAD软件,设计出了左前柱下部加强板冲压成形的5副模具。通过预压成形,制件符合各项技术指标。     

汽车行李箱盖外板回弹控制的工艺研究

针对汽车行李箱盖外板在冲压成形过程中容易出现回弹的问题,以某车型行李箱盖外板为例,通过优化制件的翻边工艺,有效地控制了制件回弹,同时,采用Autoform软件对优化前后的制件回弹进行模拟分析对比,结果表明,翻边工艺的改进可以有效改善回弹,避免了A面补偿带来的表面质量缺陷,可为车门外板或发动机罩外板的外覆盖件的冲压成形提供参考。     

翼子板翻边整形复合斜楔结构设计

介绍了成形某车型翼子板第3道工序中的翻边整形复合斜楔结构,该斜楔将向下整形和侧向翻边整合在一起,减少了模具数量,节约了制造成本。模具已投产,动作顺畅,成形的零件品质好,达到了预期效果,具有一定的推广价值。     

行李箱隔板成形工艺分析与翻边整形模设计

以汽车行李箱隔板为例,介绍了零件成形工艺、模具工作过程、双活翻边整形模结构设计要点以及模具设计注意事项,经过生产批量验证,零件生产工艺及模具结构设计合理,生产稳定,降低了模具制造成本,成形后零件尺寸精度满足客户要求。     

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.     

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.     

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.     

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.