焊接技术在动车组铝合金车体焊接的应用及发展趋势

通过对MIG焊、TIG焊、电阻点焊、激光焊及搅拌摩擦焊技术在轨道车辆铝合金车体焊接中的应用情况进行分析,阐述了上述各种焊接技术在轨道车辆铝合金车体焊接应用中的优缺点.总结得出:MIG焊及TIG焊技术是我国动车组铝合金车体制造目前应用的主要焊接技术,激光焊及搅拌摩擦焊技术在动车组铝合金车体焊接中的应用是未来我国动车组铝合金车体制造中的趋势.     

轨道车辆铝合金车体焊接现状及搅拌摩擦焊新技术应用

分析了轨道车辆铝合金车体焊接的应用现状及存在的技术问题,着重阐述搅拌摩擦焊技术在铝合金中厚板部件中的研究应用进展,并提出了搅拌摩擦焊技术在轨道车辆铝合金车体制造行业未来的发展趋势。     

轨道车辆焊接制造工艺现状及发展趋势

焊接工艺是轨道车辆生产制造的关键技术,直接影响到车辆品质、制造成本和生产周期.本文对轨道车辆铝合金车体、不锈钢车体、转向架构架焊接制造工艺现状进行了分析,探讨了焊接新工艺的应用前景及发展趋势,对提升车辆焊接制造技术水平提出了方向性指导.     

轨道车辆铝合金车体自动焊接气孔研究

分析了轨道车辆铝合金车体自动焊接气孔缺陷产生的机理,研究了导致焊接气孔产生的影响因素,提出了有效控制铝合金车体自动焊接气孔缺陷产生的措施,为自动焊接技术发展提供技术借鉴。     

7020铝合金应用于轨道车辆的焊接工艺研究

为了研究7020铝合金在轨道车辆行业应用的可行性,针对该合金的特点制订了18mm厚度的7020-T6铝合金的对接焊接工艺.在焊接试验过程中分别尝试采用了6系铝合金焊接常用的三元气(70％Ar+30％He+0.015％N2)和新应用的二元气(70％Ar+30％He)作为焊接保护气体,焊后进行了外观检测、渗透检测和X射线检测及理化检测.试验及检测结果表明,6系铝合金的焊接工艺基本适用于7020铝合金的焊接;采用三元气和二元气作为保护气体焊接的接头抗拉强度相当,分别达到282.5和280 MPa,明显高于20 mm厚6082铝合金焊接接头对应的261和237.5 MPa的抗拉水平,且弯曲性能均能达到标准要求,证明了7020铝合金在轨道车辆车体焊接中具有应用的可行性.     

轨道车辆铝材的性能及尺寸(1)

铝材在轨道车辆制造中获得了广泛的应用,高速铁路(简称高铁)与磁悬浮列车的车体全是用铝合金制造的,城轨车辆及地铁车辆也有约40％为铝合金的,专用运煤及其他矿产品车辆也可用铝合金制造.制造铝合金轨道车辆的铝材主要有板、带、箔、型、管、棒材与锻件等.板材主要是用5754、5083、5052等铝合金生产,型材主要是用6063、6N01、6082、6061、7003、7N01等铝合金生产,生产锻件的合金有6061、6110A、5083等铝合金.对这些合金材料的力学性能以及欧盟的有关标准进行了介绍.在选择铝合金时应综合考虑强度性能、使用性能、耐用性能、物理性能、可焊接性、成形性能、抗腐蚀性能和成本等因素.全文分为三部分刊出,本篇对生产轨道车辆板材和挤压材的5×××系铝合金进行介绍.     

激光加工技术在轨道车辆制造中的应用

本文介绍了激光加工技术在轨道车辆制造领域的应用现状及前景分析,详细说明激光在不锈钢板材、铝合金板材、合金钢板材备料工序及激光加工技术用于不锈钢车体焊接、焊接构架自动化焊接生产线、质量体系建设之标识移植等应用成果,介绍了激光作为一种新能源在不锈钢车体焊接、高速动车组铝合金车体焊接及高速转向架焊接的研究进展,已完成5083、6005A、6N01、7N01、SMA490BW等材料的焊接接头性能研究,并建立了焊接规范数据库,完成了车体端墙、端部侧墙、转向架侧梁、纵向梁等激光复合焊焊接样件的试制。     

轨道车辆自动焊接调试技术及焊接缺陷分析与控制(三)

作为轨道车辆自动焊接调试技术及焊接缺陷分析与控制系列专题之一,本文专题研究了轨道车辆铝合金车体部件在焊接过程中所产生的焊缝表面发黑一类问题。通过结合实例进行分析,研究了不同类型焊缝表面发黑问题的成因,研究证明:焊缝表面发黑主要与焊接时焊枪高度、气体流量、弧长以及送丝速度等焊接工艺参数因素有关。     

轨道车辆焊接结构轻量化发展趋势概述

近10年,是我国轨道车辆装备研制水平发展最快的时期,轨道车辆制造业技术装备及工艺水平显著提高,达到了国际先进水平。车辆车体的制造材料实现了从碳钢向不锈钢、铝合金材料的转变。车辆节能、环保、轻量化概念日益成为轨道行业技术创新的重点发展方向。文中主要从焊接工艺、焊接结构疲劳强度分析轨道车辆轻量化发展现状及趋势。     

轨道车辆专用铝合金焊丝研制成功

<正> 最近,轨道车辆专用铝合金焊丝在杭州银宇焊接材料科技有限公司试制成功,经产品检测和焊接试验,产品的合金成分、内部组织、表面质量和焊缝强度、抗弯曲性、热裂纹影响等技术指标均达到国际先进产品水平,完全可替代进口产品用于轨道车辆的焊接。目前,公司正在组织小批量生产,预计2010年12月可投放市场。随着中国铁路交通的迅速发展,轨道车辆大部分已采用铝合金制造,由于对安全性能要求很高,其专用铝合金焊丝目前国内还没有生产企业,全部依赖高价进口,而国外生产技术也只有美国、加拿大、日本、英国     

铝合金轨道车辆结构及合金性能(1)

本文分为两篇刊登,本篇介绍了城市轨道交通和高速铁路在节能减排方面的优势及铝合金车体的优越性;综述了铝合金车体制造的关键技术和所用的铝合金材料;对国内外的一些铝合金车辆用型材及车体结构作了简要介绍。     

铝合金轮辋焊-锻复合成形的可行性研究

分析了铝合金焊一锻复合成形工艺对车辆减重的意义,以其在轮辋零件的应用为背景,针对三种硬铝材料2014、2024及2219,采用MIG焊接方法.对其3mm厚板进行了鱼骨形裂纹试验,并对其4mm厚板分别用同质焊丝进行焊接,比较了三种铝合金焊接接头热处理前后的力学性能,由此选择出2219铝合金最适合用来进行轮辋的焊一锻复合成形.     

汽车工业中的铝合金及其焊接技术

铝及其合金在汽车工业的应用中具有轻量化、节能减排、改善环境、提高汽车平稳性和安全性等特点。铝及其合金熔化焊存在焊缝易产生气孔,焊接接头易软化等缺陷。讨论了激光-电弧复合焊、激光拼焊、搅拌摩擦焊在汽车用铝及其合金焊接的应用和特点。     

Effect of Postweld Aging Treatment on Fatigue Behavior of Pulsed Current Welded AA7075 Aluminum Alloy Joints

This article reports the effect of postweld aging treatment on fatigue behavior of pulsed current welded AA 7075 aluminum alloy joints. AA7075 aluminum alloy (Al-Zn-Mg-Cu alloy) has gathered wide acceptance in the fabrication of light weight structures requiring high strength-to weight ratio, such as transportable bridge girders, military vehicles, road tankers, and railway transport systems. The preferred welding processes of AA7075 aluminum alloy are frequently gas tungsten arc welding (GTAW) process and gas metal arc welding (GMAW) process due to their comparatively easier applicability and better economy. Weld fusion zones typically exhibit coarse columnar grains because of the prevailing thermal conditions during weld metal solidification. This often results inferior weld mechanical properties and poor resistance to hot cracking. In this investigation, an attempt has been made to refine the fusion zone grains by applying pulsed current welding technique. Rolled plates of 10 mm thickness have been used as the base material for preparing multipass welded joints. Single V butt joint configuration has been prepared for joining the plates. The filler metal used for joining the plates is AA 5356 (Al-5Mg (wt.%)) grade aluminum alloy. Four different welding techniques have been used to fabricate the joints and they are: (i) continuous current GTAW (CCGTAW), (ii) pulsed current GTAW (PCGTAW), (iii) continuous current GMAW (CCGMAW), and (iv) pulsed current GMAW (PCGMAW) processes. Argon (99.99% pure) has been used as the shielding gas. Rotary bending fatigue testing machine has been used to evaluate fatigue behavior of the welded joints. Current pulsing leads to relatively finer and more equi-axed grain structure in GTA and GMA welds. Grain refinement is accompanied by an increase in fatigue life and endurance limit. Simple postweld aging treatment applied to the joints is found to be beneficial to enhance the fatigue performance of the welded joints.     

Laser welding of complex aluminium structures

Abstract

Automotive manufacturing is making significant strides towards producing lighter but stronger vehicles. Developments in high strength steels and lightweight materials, especially aluminium, have contributed to these advances. The body shell contributes nearly 25% of a car's weight. Current predictions estimate the contribution of aluminium in a car to be of the order of 10% of the total vehicle weight, whereas the use of aluminium alloys in car body manufacture could lead to potential weight savings of up to 43%. The use of aluminium is expected to grow in body in white and tailored welded blank applications within the automotive sector. Complex joint configurations are encountered in spaceframe assembly. One such joint structure, which involves the welding of a rectangular section to a flat plate, has been considered in the work reported. Traditionally, a MIG welding solution would be adopted to manufacture such a joint. Work was performed to establish the feasibility of using laser welding to manufacture the component and to compare the laser and MIG processes. A fibre optic delivered Nd-YAG laser beam, manipulated with an articulated arm robot, was successfully used to weld the tube to the aluminium plate. Spatter free welds with no externally visible porosity were achieved and no cracking was observed in any weld cross-section examined. Mechanical tests indicated that the static strength of the laser welds was lower than that achieved by MIG welding, which is attributed to the lower load bearing area in the laser welded joints.     

铝合金车体制造关键技术研究

全铝结构铝合金车体正逐步在中国各城市的轨道车辆、铁路高速动车组上推广应用,制造高质量的铝合金车体是保证车辆运行的必要条件文章.论述了制造铝合金车体的关键技术和各种工艺方法的局限性,指出灵活运用工艺方法的规则.     

TIG焊工艺对LD10铝合金接头气孔的影响

LD10铝合金是国内航天运载器推进剂贮箱的主要应用材料,通常采用钨极氩弧焊(TIG焊).气孔是铝合金熔焊接头中的常见缺陷,文中对5.5 mm厚的LD10铝合金进行了4种不同工艺条件的TIG焊接,对比研究了4种工艺接头的气孔问题.结果表明,LD10铝合金采用TIG焊时,容易产生气孔,其中两面三层焊接头X射线检测出的不合格焊缝相对较多;对于合格焊缝中的微气孔而言,两面三层焊较少,其次是两面两层焊和单面两层焊,单面单层焊最多,它们的气孔率分别为0.90%,2.28%,2.53%,3.28%.焊缝气孔较多时,在接头横向拉伸试验中裂纹容易从气孔启裂.     

Welding equipment for reinforcing the edges of corrugated walls of the casings of transformers of a new generation of TMG series

The application of aluminium alloy, which is a typical lightweight material, has been expected in the construction of transportation vehicles to achieve energy saving by reduction of weight. However, structures made of whole aluminium alloy have problems with low strength and high cost. Thus, hybrid structures made of Al alloy and steel are useful because of light weight and higher strength. To construct the hybrid structure, it is necessary to weld aluminium alloy and steel. However, conventional welding methods, like brazing and mechanical fastening, have problems such as low mechanical strength and low productivity. Also, it is difficult to weld Al alloy and steel by conventional fusion welding.

In this study, spot welding between aluminium alloy and low carbon steel by friction stirring was carried out. Especially, optimization in welding conditions was carried out. Moreover, the effect of welding conditions on the joint strength and weld interface was studied. As a result, relatively higher tensile shear strength of the weld, which was achieved at optimum welding conditions, was obtained. Temperature near weld interface measured by K-type thermocouple during welding was found to be lower than the melting point of A5052. From the observation results on microstructure of the weld interface, it was found that a Fe/Al intermetallic compound layer was formed.     

单一成分活性剂对铝合金作用效果的研究

活性化TIG(A-TIG)焊已成为近年来的研究热点,但主要集中在不锈钢和钛合金两种材料,在铝合金中的应用较少.针对铝合金A-TIG焊进行了初步的研究和探索,选择四种单一成分的活性剂,采用表面两侧涂敷方式,通过2A14铝合金的平板堆焊实验,研究了在相同规范下不同活性剂对焊缝熔深、焊缝成形、气孔和微观组织的影响.实验结果表...