深孔加工技术研究进展

深孔加工技术是机械加工中一项重要的技术,在石油化工、航空航天、造船工业、核电管板、电力设备等大部分制造部门有着广泛的应用。同时深孔加工具有排屑难、导热差、冷却润滑难等问题。本文从现代制造业对于深孔加工的需求出发,阐述了深孔加工系统发展与特点,重点对BTA系统、吸喷钻系统及DF系统进行分析;分析了不锈钢、钛合金、镍基合金等不同材料的深孔加工特点,及所用刀具材料的选择;对深孔加工状态监测的国内外研究现状进行概述。在此基础上,本文指出钻头结构的优化设计及高性能钻头材料的研发是深孔加工技术发展的主要方向。     

深细孔与超深孔电化学加工技术应用分析

介绍了军用武器装备及民用产品中深孔结构的加工难点及国内外深孔电化学技术的应用现状,重点论述了深细孔及超深孔等结构的电化学加工的可行性及技术优势。     

弯孔加工技术发展与展望

针对现阶段热成形模具冷却孔多采用深直孔的现状,介绍了国内外现有的弯孔加工技术与研究现状,围绕采用各种特殊方式对弯孔加工的关键技术进行了论述。分析了各种弯孔加工方式所存在的问题,揭示了弯孔加工的主要技术难点,并对今后的弯孔加工技术发展做出了展望。     

20世纪深孔加工技术的兴衰及新突破——介绍SIED深孔加工集成技术

回顾20世纪深孔加工技术的兴起及其对国际制造业的贡献.剖析20世纪80年代后深孔加工技术出现停滞衰落的症结.简要介绍SIED技术,展望21世纪深孔加工技术的发展和应用前景.     

深孔精密液压元件内孔加工工艺的研究

深孔精密液压元件加工的关键在于深孔的精密加工。目前国内深孔加工技术尚未成熟,此类产品绝大部分只能依靠进口。结合某公司伺服油缸、高压油缸、摆动缸深孔元件的加工,通过对密封机制与密封失效的分析,阐述深孔精密液压元件深孔精密加工的重要性,提出深孔精密元件加工的工艺路线。     

深孔加工技术的基本资料

深孔加工与通常的麻花钻加工相比较,其最大的差异点是排屑和刀刃的冷却都很困难。深孔加工最主要的是,在不中断切削的条件下,以最高的切削速度和进气量,能够加工完孔的全长,在近几年的研究和改进的结果,采用深孔加工能够实现很高的生产率。另外,随着气动液压机械的发展,深孔镗技术也和一般深孔(一般深孔大于孔径的10倍以上时,叫深孔加工)加工一样得到了很大的进展。     

核电大汽缸复合角度深孔加工工艺研究与应用

核电大汽缸是核电机组的基础部件,汽缸体上的复合角度斜深孔加工是汽缸体加工的重难点。通过分析复合角度斜深孔的加工难点和加工现状,着重从加工方法、加工刀具、装夹方式、冷却润滑等方面进行详细研究,将专用工装与铲钻技术相结合,成功完成复合角度斜深孔的加工,满足产品加工要求,从根本上解决了核电大汽缸复合角度斜深孔的加工技术难题。     

基于SINUMIRIK系统的递减式深孔加工研究

深孔加工过程中断屑、排屑和散热问题,是深孔加工的关键技术问题。在分析采用SINUMIRIK 840D系统钻孔循环进行深孔加工存在的不足之处的基础上,提出递减式深孔加工的原理和设计思路,并结合R参数和CYCLE83深孔钻循环指令开发了递减式深孔加工的通用子程序,从工艺上弥补了CYCLE83循环的缺陷,解决了固定钻深的技术问题,有较高的生产实用价值。     

深孔加工技术在管制造业中的扩展应用

介绍了深孔加工SIED技术在管制造业中的应用,提出了和冷拔冷轧等技术相结合的方法来制造各种常规孔加工技术难以加工的超深或微小超长精密管件.     

深孔钻机床在模具加工中的应用

1.前言随着数控机床及加工中心等设备在我国的普及。模具加工高效率和高速化的发展过程中,对模具冷却水孔、顶杆孔进行深孔加工的数控深孔钻床也越来越引起人们的关注。占模具机加工工作量20～30％的钻孔加工设备,到目前为止大多仍采用摇臂钻机床。这就阻碍模具生产向大型化、高效率发展。下面就深孔钻机床的概况,加工特点和加工方法作一介绍。深孔钻机床如图所示。     

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.