精密级进模制造工艺及设计中应注意的问题

<正> 1 精密级进冲模的主要制造工艺 精密级进冲模凹模板(镶块结构中指凹模     

德国STEPPER公司级进模设计制造技术概述

德国ＳＴＥＰＰＥＲ公司级进模设计制造技术概述机械部桂林电器科学研究所（５４１００４）王家庆机械部桂林电器科学研究所模具分所近２年来引进了德国ＳＴＥＰＰＥＲ公司的ＫＩＷＩ软件、设计技术、加工工艺以及加工设备。并以ＳＴＥＰＰＥＲ公司的ＳＴＥＰＰＥＲＭＯＤ...     

成形冲孔级进模设计

<正> 1 零件的工艺分析 压板零件如图1所示,材料10钢板,厚1mm,零件孔间距精度要求较高。     

薄料精密多工位级进模设计

薄料精密多工位级进模设计烟台海通电子有限公司张业媛，董文明图１所示是ＣＢＭ—２２３Ｐ双联薄膜介质可变电容器的动片。该零件材料为电容器专用铝带ＬＴ，厚度０．２±０．０１ｍｍ，其外形复杂，由多处不同的圆弧和直线组成，尺寸精度和形位公差要求高，其技术要求：...     

定接触片级进模设计

定接触片级进模设计贵州凯里市８５１厂谢又炎图１是我厂某开关的定接触片零件，材料为锡青铜，厚度ｔ＝０．２５ｍｍ。该零件原成形工艺为：落料→第一次弯曲→第二次弯曲。故以往生产中，除效率较低外，由于零件外形尺寸较小，中间工序多，定位基准不统一而使零件尺寸一...     

多工位级进模设计入门(七)

<正> 四 设计注意事项1 冲裁间隙 冲裁间隙的大小,不但影响冲件的剪断面形状(见《冲模设计手册》第41页的图3—5)——包括毛面斜度、塌角、毛刺等等,而且也影响冲落体和冲出孔的尺寸精度。多工位级进模所冲裁的材料都是薄料,一般在0.1～2.5mm范围内,而以1mm左右的为多。因此剪断面的质量要求是次要的,而尺寸精度是主要的。 关于冲裁间隙,有部颁指导性技术文件     

少废料级进模设计

<正> 1 引言图1所示支架零件,原工艺为落料→冲孔→弯曲→钻 M2mm 底孔→攻丝,不仅工序分散,浪费人力、财力,而且在装配时发现有些零件丝孔滑丝。经分析,认为滑丝主要是由丝孔浅及螺纹底孔超差所致。     

管形散热器镶拼式级进模

管形散热器镶拼式级进模上海金陵股份有限公司散热器分公司（２０００２０）王波海１概况图１是铝板材４０２管形散热器，该零件原生产工艺流程为：①落料冲孔；②折边；③Ｕ形弯曲；④Ｏ形弯曲。现改为级进模成形，模具结构见图２。排样图见图３。模具优点：精度高，可连...     

级进模结构设计中的几个问题

扼要叙述在设计级进模时常用的一些落料复位、定距、导料、定位等方面的结构形式。     

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.