电子束焊接在齿轮行业中的应用

一、电子束焊接原理与特点电子束焊接是利用汇聚的高速电子流轰击工件接缝处所产生的热能 ,使金属融合的一种焊接方法。电子束是从电子枪中产生的。通常电子是以热发射的方式从发射体 (阴极 )逸出。在 2 5～ 30 0ｋＶ电压的作用下 ,电子被加速到 0 .3～ 0 .7倍的光速 ,具有极大的动能。经电子枪中静电透镜和电磁透镜的作用 ,电子汇聚成能量密度很高的电子束。这种电子束撞击到工件表面 ,电子巨大的动能就转变为热能 ,使金属迅速融化和蒸发。在高压金属蒸汽的作用下融化的金属被排开。电子束就能继续撞击深处的固态金属 ,很快在被焊工件上钻…     

电子束焊接在传动系统零件制造中的应用

简要介绍了电子束焊接在传动系统中的双联齿轮、齿轮轴、框架高精度零件加工中的应用。电子束焊接作为焊接领域内的一项高新技术已在国外获得广泛应用,为推广此项技术,本文以典型实例介绍了电子束焊在齿轮类零件、框架类零件加工等方面的应用,分析了影响焊接质量的因素,并给出了解决方案。实践证明,电子束焊接是一种能满足高质量产品焊接的特种焊接方法,具有传统焊接方法不可替代的优越性。     

激光焊接胜过电子束焊接

Michigan公司把原先用电子束(EB)焊接生产汽车、宇航和医疗器械用零件的有些部位,现在已改用激光焊接。虽然,电子束焊接的质量最好,但Special WeldingServices(SWS)公司所用的激光焊接其效率要比电子束焊接高出2～3倍,其焊接质量也类似电子束的焊接质量,且正常生产时间可达95％。 EB焊接在真空中进行,故焊接污染不大,零件变形最小,同时有大的焊接深宽比。可惜的是这一过程耗时太多,还要求在铅衬的小室内工作,以防发出的射线影响四周。而且,真空室的大小,限制了所能焊接的零件尺寸。 SWS的总裁Jay Morley说:“我们看到了对EB焊接质量所唤起的要求,但是,这种技术的成本和处理时间对任何产量的成本都过高。”     

电子束焊接在齿轮加工中的应用

对电子束焊接的特点、工艺要求进行了简述,并通过实例说明这种焊接方法在齿轮加工中的应用场合,采用电子束焊接时各齿轮组件的加工工艺要求及工艺过程。实验结果表明,该工艺扩大了设备的加工能力,提高了设备的利用率。     

电子束焊接

电子束焊机始于60年代，至今已研制生产出不同类型和功能的电子柬焊机，能为国内市场提供小功率的电子束焊机。     

ZD系列电子束焊接技术及应用

国内电子束加工技术近年来得到了快速发展,并广泛地应用于制造工业中,特别是在武器装备制造方面.文章介绍了ZD系列电子束焊接设备和工艺技术的发展情况及其应用.     

电子束焊接技术的应用

近几年 ,我厂开发出日本五十铃系列ＭＳＡ、ＭＳＢ数种汽车变速器及ＴＣＭ叉车变速器 ,其产品的技术水平在国内处于领先地位。在齿轴零件的制造过程中 ,有些零件考虑其结构及加工工艺性 ,大胆采用了国内先进的电子束焊接技术 ,应用效果较为显著 ,既提高了产品质量 ,又降低了生产成本。　　一、设备概况1.我厂现采用的电子束焊机是北京中科电气高技术公司生产的低真空齿轮焊接专用设备 ,型号为ＥＢＷ— 4ＧＣ ,焊接具有可靠的自动运行程序系统 ,操作方便、焊缝质量优良、重复精度高。2 .设备的电子束加工原理 ,是由灼热阴极所发射的电子流在…     

真空吸具在球壳电子束焊接中的应用

分析球壳电子束焊接装夹的特点,运用真空吸具的优点,设计出一种快速、精确可靠的真空吸具辅助装夹系统,解决了长期以来球壳电子束焊接装夹找正难的问题。     

TA15钛合金电子束焊平行焊缝的获得方法

截面平行的焊缝是保证中大厚度焊接结构熔合区组织均匀性及力学性能连续性的重要条件,在工程中有着重要应用。本文在对焊缝形貌进行观察及分析的基础上,研究获得平行焊缝的工艺方法。结果表明,对焊接速度、电子柬流及聚焦电流等焊接参数进行综合调节,可以有效改变焊缝形貌,使焊缝逐步趋于平行。增加编摆扫描并控制扫描的频率和幅度,可以获得一系列具有不同熔宽的平行焊缝。     

电子束钢带镀膜技术探讨

介绍国内第一条电子束钢带镀膜生产线的情况 ,对钢带镀膜的一些工艺及设备技术问题进行分析探讨。     

电子束选区熔化技术的控制系统设计

通过对电子束选区熔化技术控制系统的功能需求进行分析,得到了以PMAC数控卡作为控制系统下位机的控制方案,不仅可以对4个步进电机及限位信号进行运动控制,而且可以进行扫描数据的存储、下载、计算及运行.两年多的运行表明该控制方案具有较高的可靠度.     

Using a principal components analysis for developing a robust design of electron beam welding

This paper presents the application of principal components analysis for Taguchi orthogonal experiments to develop a robust electron beam welding treatment (EBWT) process with high efficiency multiple performance characteristics (MPCs). In this study, the principal components analysis (PCA) design incorporating the correlation matrix of tested trials is employed. In the first step, the MPCs are reduced to two independent components using PCA. Both components accounted for 98.8% of the total variance. The first principal component (PC), which refers to the integrated hardening capability index of the EBWT process, accounts for 70.7% of the total variation. The remaining 28.1% were contributed by the second PC, which can be interpreted as the penetration capability index. In the second step, we identify the most important PC loading vectors using PCA, and estimate the importance of the PCs. By using PCA, relationships between different MPCs can be investigated and the most important factors for the variance of the EBWT process can be identified. The experimental results show that redundant information could be eliminated by using principal components in conjunction with Taguchi’s orthogonal array experiments. This proposed approach is simple, effective, and efficient for developing a robust and high-efficiency EBWT process of high quality. In this study, the MPCs in the EBWT process are successfully optimized .     

Focused ion beam scanning electron microscopy in biology

Since the end of the last millennium, the focused ion beam scanning electron microscopy (FIB‐SEM) has progressively found use in biological research. This instrument is a scanning electron microscope (SEM) with an attached gallium ion column and the 2 beams, electrons and ions (FIB) are focused on one coincident point. The main application is the acquisition of three‐dimensional data, FIB‐SEM tomography. With the ion beam, some nanometres of the surface are removed and the remaining block‐face is imaged with the electron beam in a repetitive manner. The instrument can also be used to cut open biological structures to get access to internal structures or to prepare thin lamella for imaging by (cryo‐) transmission electron microscopy. Here, we will present an overview of the development of FIB‐SEM and discuss a few points about sample preparation and imaging.     

Measurement of electron probe beam diameter by digital image processing

The present report illustrates a computerized method for precise measurement of the diameter of an electron beam. The value of this measurement extends beyond simply providing an accurate estimate of resolution. Other salient areas which will benefit include quantitative X-ray microanalysis, energy loss spectroscopy, diffraction studies, and electron beam lithography. The biological sciences as well as the material sciences will gain enormously from improved accuracy in measurement (control) of beam diameter. It is anticipated that most or all of the mathematical manipulations outlined in this paper will be incorporated into digital electronic packages which will perform the functions automatically for setting the electron beam diameter to the scientist's choice. The purpose of the present report is to indicate some of the principles involved so that as electron microscopy becomes more computerized and automated, the user will have some understanding of what the electronics are doing rather than simply depressing a button or two and ignoring the power of what resides within the walls of the instrument. The performance of a scanning electron microscope (SEM) and a scanning transmission electron microscope (STEM) is roughly determined by the incident electron probe beam size (diameter) involving a sufficient electron current. In the present paper, the diameter of an ultrafine electron beam is measured indirectly from the information given by the blurring of an edge in a STEM or a SEM image of a crystalline specimen with fine, sharp edges. The obtained data were processed by digital image processing methods which give an accurate value of the beam diameter. For confirming the validity of this method, a suitable simulation based on the convolution theorem was performed. By using this measurement, we could measure the diameter of an ultrafine electron beam down to 2 nm, which could not be measured easily by previous techniques.     

电子束选区熔化技术的粉末预热系统设计

通过对电子束选区熔化技术中金属粉末的预热方式进行分析和比较,得出了成形底板采用加热板和成形活塞缸上部采用环形加热器进行粉末预热的两种热传导方案;采用短波段的红外辐射灯,并通过旋转装置保证粉末预热和辐射灯不被金属蒸气蒸镀.金属粉末预热后的成形效果明显提高.     

GH4169合金电子束焊接接头CTOD断裂韧度

根据GB/T2358—94标准,分别在20℃和650℃下,对GH4169合金电子束焊接接头的裂纹尖端张开位移(CTOD)进行测试。取SE(B)试样进行三点弯曲试验,然后由所得到的20℃和650℃下母材和电子束焊缝的P-V曲线来计算CTOD值,比较两个温度下的试验结果,对试验结果进行了分析讨论。