某车型侧围外板整形模具设计

侧围外板是汽车的核心外覆盖件,其特点是形状极其复杂,工序内容繁多,且零件的表面质量和尺寸精度要求较高。本文通过侧围外板的冲压工艺方案分析,提出一种内嵌压料芯的整形工艺和结构,可有效解决内部或边角整形无法压料引起的整形起皱、回弹,同时达到保证零件形位公差的目的。重点讲述了侧围整形模结构、压料芯内嵌整形机构及工作原理。实际生产表明,该结构可有效解决整形起皱、回弹,提升A面品质,缩短调试周期,降低工装开发成本。     

带大型旋转斜楔在顶盖外板侧整形模具中的应用与研究

本文介绍了一种带大型旋转斜楔在顶盖外板侧整形模具中的应用与研究,通过在顶盖外板侧整形模具上采用大型旋转斜楔解决顶盖与前风窗玻璃搭接区域负角整形,实现凸模滑块放取件与侧整形状态切换,有效缩短了模具长宽方向上的工作行程,同时实现了弧形边侧整形过程料流可控,达到零件面差精度和外观质量要求。实际生产表明,该结构可有效解决整形起皱、回弹问题,有效降低模具尺寸,节约工装开发成本,缩短调试周期。     

汽车侧围外板表面缺陷分析及冲压工艺优化

汽车外覆盖件的表面质量直接影响整车的外观,是冲压成形领域关注的重点之一。针对SVW斯柯达品牌某车型侧围外板在冲压成形过程中出现的开裂、起皱、圆弧轮廓不平顺等一系列表面缺陷,从工艺设计和模具结构的角度分析了缺陷产生的原因。结合CAE模拟和现场调试,在满足试模压机和生产线压机不同工况的条件下,通过优化产品表面藏料工艺凸包,同时平衡压料力和整形力,解决了最困难的表面问题,达到了生产稳定性和产品质量的要求,并在此基础上,对工艺优化产生的经济效益进行了统计。对汽车行业侧围外板产品的零件设计、侧围冲压模具工艺和结构设计、侧围冲压模具调试均具有参考意义。     

汽车侧围外板A柱拐角起皱的分析及解决方案

汽车侧围外板零件是车身重要的冲压件之一,成形过程较复杂,拉深过程中易产生起皱、开裂等缺陷。针对汽车侧围外板A柱拐角部位的起皱、开裂问题,通过分析零件现场冲压工艺、A柱拐角部位变形特征和材料发生起皱的原因,建立有限元仿真模型,使用AUTOFORM模拟软件对原冲压工艺方案进行全程仿真,分析结果表明,在第3工序侧整形时拐角处的流水槽面发生严重起皱缺陷。系统研究了二次拉深工序中增加吸料筋和调整压边力对起皱、开裂的影响规律,并提出在侧围外板A柱拐角处增加吸料筋和调整压边力的整改方案。经现场生产验证了分析结果的准确性和修模方案的有效性。     

汽车车门内板冲压工艺方案及修边整形模设计

介绍了一种汽车车门内板冲压工艺方案,以及上模带双模腔特征、多压料芯结构的轿车车门内板修边整形模的应用,通过对车门内板冲压工艺及模具结构分析,采用拉深后先整形再周圈修边的工艺方案,并结合CAE仿真模拟分析进行产品结构及工艺模面优化,有效解决了成形开裂及起皱问题。在修边整形模中,采用内外双排侧销控制的内压料芯及左/右外压料芯结构,使待整形区域整形时两侧同时压料,整形时发生胀形及加工硬化,在产品形状实现的同时,也可促进产品周圈刚性的提升,减少回弹变形。实际生产证明,该冲压工艺方案有效可行,已实现大批量生产,车门内板单件精度、品质及包边总成效果都较好。     

夹料翻边及整形调试方法

夹料翻边及整形工艺是模具制造过程中重要的工艺方法,这种工艺方法在顶盖天窗、门外板及侧围等汽车大型外覆盖件模具中使用较为广泛;对改进产品回弹和面品质量有较大的提升作用,通过调整夹料间隙的方式方法来改善外板回弹及面品质量有较为显著的效果。     

侧围外板起皱分析及模具改进

针对某款轿车的侧围外板暴露面起皱的问题,分析其产生起皱的原因,对制件和冲压模具工艺及模具结构提出了改进可行分析,并实施措施,应用在生产现场,从而彻底消除侧围外板暴露面起皱现象。     

侧围外板顶盖搭接处冲压新工艺的应用

侧围外板是白车身制造过程中的关键,探讨合理的工艺方案可以避免产品A面产生二次冲击线,减少焊接边翻边整形时起皱叠料现象,确保产品料边稳定一致,保证产品质量。     

轿车侧围外板表面起皱现象的工艺改进

针对上海大众汽车普通桑塔纳轿车的侧围外板暴露面起皱的问题，分析其产生起皱的原因，对原模具结构和冲压工艺提出了改进方案及实施措施，应用在生产现场，从而彻底消除侧围外板暴露面起皱现象。     

双层滑块结构在汽车侧围外板模具上的应用

介绍了一种双层滑块及压料板带滑块在汽车侧围外板翻边模中的应用,通过对侧围外板冲压工艺及模具结构的分析,实现了侧围外板侧翻边与其他工序在同一副模具上的成形,还叙述了双侧滑块及压料板带滑块结构的工作原理,该结构降低了模具的开发成本,节省了冲压车间场地的占用面积,提高了工作效率。     

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.     

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).     

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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Antimony Induced Crystallization of Amorphous Silicon

Antimony induced crystallization of PVD (physics vapor deposition) amorphous silicon can be observed on sapphire substrates. Very large crystalline regions up to several tens of micrometers can be formed. The Si diffraction patterns of the area of crystallization can be observed with TEM (transmission electron microscopy). Only a few and much smaller crystals of the order of 1μm were formed when the antimony layer was deposited by MBE (molecular beam epitaxy) compared with a layer formed by thermal evaporation. The use of high vacuum is essential in order to observe any Sb induced crystallization at all. In addition it is necessary to take measures to limit the evaporation of the antimony.     

A CUMULATIVE FATIGUE DAMAGE RULE UNDER THE ALTERNATIVE OF CORROSION OR CYCLIC LOADING

Fatigue damage increases with the applied loading cycles in a cumulative manner and the material deteriorates with the corrosion time. A cumulative fatigue damage rule under the alternative of corrosion or cyclic loading was proposed. The specimens of aluminum alloy LY12-CZ soaked in corrosive liquid for different times were tested under the constant amplitude cyclic loading to obtain S-N curves. The test was carried out to verify the proposed cumulative fatigue damage rule under the different combinations among corrosion time, loading level, and the cycle numbers. It was shown that the predicted residual fatigue lives showed a good agreement with the experimental results and the proposed rule was simple and can be easily adopted.