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镁合金搅拌摩擦焊接技术的研究进展 总被引:4,自引:0,他引:4
搅拌摩擦焊是利用一种特殊形式的搅拌头边旋转边前进,通过搅拌头与工件的摩擦产生热量,摩擦热使该部位金属处于热塑性状态,并在搅拌头的压力作用下从其前进端向后部塑性流动,从而使待焊件压焊为一个整体.由于搅拌摩擦焊是固态焊接,所以没有熔化焊时的气孔、裂纹等缺陷.综述了镁合金搅拌摩擦焊接技术的新进展,并对镁合金搅拌摩擦焊接技术的发展进行了展望. 相似文献
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《机械制造文摘:焊接分册》2016,(2)
采用小孔法分别对6 mm厚度7020铝合金的熔化极气体保护焊及搅拌摩擦焊对接接头的残余应力进行了测试。结果表明,用两种焊接方法得到的焊接接头,其纵向应力均大于横向应力,对比7020铝合金搅拌摩擦焊接头和熔化极气体保护焊接头中的纵向残余应力,发现搅拌摩擦焊接头的纵向残余应力峰值要远远小于熔化极气体保护焊接头中纵向残余应力峰值。搅拌摩擦焊接头的最大纵向残余应力为50 MPa,而熔化极气体保护焊接头的纵向残余应力最大值已经达到了90MPa。 相似文献
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郁志凯梁晨毛孟颖钮旭晶 《电焊机》2022,(10):62-71
对分别采用搅拌摩擦焊和熔化焊的连接板焊接接头的金相、拉伸、弯曲、硬度及疲劳性能等方面进行对比研究。两种焊接方式金相均合格;采用搅拌摩擦焊的连接板接头抗拉强度为275.67 MPa,比熔化焊(263.8 MPa)高约4.5%;搅拌摩擦焊接头弯曲性能侧弯180°均合格,熔化焊接头侧弯试件在110°左右时由于存在气孔导致裂纹出现;搅拌摩擦焊接头的硬度分布近似W形,中心层焊核区显微硬度值约为79~104 HV,在-18~-6 mm和6~18 mm范围内出现软化现象,最低硬度为69 HV,熔化焊接头的中心层焊缝区显微硬度值约为92~97 HV,在3~9 mm范围内出现软化现象,最低硬度为71 HV;搅拌摩擦焊接头中值疲劳极限为137 MPa,比熔化焊(117 MPa)高约17%。 相似文献
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提出了双面搅拌摩擦焊这种新的焊接方法,对比研究了6K32-T4铝合金搅拌摩擦焊与双面搅拌摩擦焊接头的组织和硬度,并对双面搅拌摩擦焊焊缝进行了XRD分析。研究发现:铝合金双面搅拌摩擦焊与搅拌摩擦焊焊缝组织分区相同;双面搅拌摩擦焊焊缝的硬度略低于搅拌摩擦焊,且焊缝硬度下降区域范围更大;双面搅拌摩擦焊后焊缝依然保持为原有相组成;双面搅拌摩擦焊比搅拌摩擦焊焊接线能量更大,采用双面搅拌摩擦焊代替搅拌摩擦焊有利于提高焊接效率并消除焊缝隧道型缺陷、改善焊缝的性能。 相似文献
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通过大量试验研究了防锈铝LF21搅拌摩擦焊接技术,深入分析了防锈铝搅拌摩擦焊接头的金相组织和力学性能,并探讨了焊接参数对组织性能的影响.对于3mm厚的防锈铝板,优化的搅拌头材料为ICr18Ni9Ti,形状为圆锥带凹面形,轴肩尺寸为φ12mm,焊针跟部直径为4mm,焊针端部直径为2.8mm,焊针高度为2.7mm.优化的焊接工艺参数范围为旋转速度950-1 500 r/min,焊接速度37.5~60mm/min.研究的成果可应用于有色金属材料搅拌摩擦焊接参数的优化,推动中国搅拌摩擦焊接技术在铝焊接中的应用. 相似文献
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Friction stir welding (FSW) is a relatively new welding process that may have significant advantages compared to the fusion processes as follow: joining of conventionally non-fusion weldable alloys, reduced distortion and improved mechanical properties of weldable alloys joints due to the pure solid-state joining of metals. In this paper, a three-dimensional model based on finite element analysis is used to study the thermal history and thermomechanical process in the butt-welding of aluminum alloy 6061-T6. The model incorporates the mechanical reaction of the tool and thermomechanical process of the welded material. The heat source incorporated in the model involves the friction between the material and the probe and the shoulder. In order to provide a quantitative framework for understanding the dynamics of the FSW thermomechanical process, the thermal history and the evolution of longitudinal, lateral, and through-thickness stress in the friction stirred weld are simulated numerically. The X-ray diffraction (XRD) technique is used to measure the residual stress of the welded plate, and the measured results are used to validate the efficiency of the proposed model. The relationship between the calculated residual stresses of the weld and the process parameters such as tool traverse speed is presented. It is anticipated that the model can be extended to optimize the FSW process in order to minimize the residual stress of the weld. 相似文献
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搅拌摩擦焊(Friction Stir Welding,FSW)是近些年发展起来的一种固态连接工艺,尤其适用于铝合金材料的焊接。概述了搅拌摩擦焊的局限性,主要包括接头处存在钥匙孔、焊缝减薄等缺陷及复杂结构铝合金难以焊接等问题。研究表明,通过工艺方法、流程及参量的优化能够对焊接接头缺陷和焊件结构问题进行有效控制。由此,归纳了铝合金搅拌摩擦焊接头存在的关键问题及解决策略,分析了每种工艺方法的适用对象及条件,包括摩擦塞焊(Friction Plug Welding,FPW)、填充式搅拌摩擦焊(Filled Friction Stir Welding,FFSW)、回抽式FSW、静止轴肩搅拌摩擦焊(Stationary Shoulder Friction Stir Welded,SSFSW)、沉积式FSW、双轴肩搅拌摩擦焊(Bobbin Tool Friction Stir Welding,BT-FSW)和无倾角FSW。详细探讨了每种工艺的原理和机制,阐述了每种工艺的优缺点,重点介绍了工艺的参数优化调控、辅助设备的添加及工序的改进对修复接头组织与力学性能的影响。对铝合金搅拌摩擦焊的回顾总结,将为获得高质量搅拌摩擦焊接头,实现复杂结构件焊接提供参考依据。在此基础上,对铝合金搅拌摩擦焊现存问题及挑战的解决进行了展望。 相似文献
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Friction stir welding (FSW) is a solid-state welding process which is capable of joining materials which are relatively difficult to be welded by fusion welding process. Further, this process is highly energy-efficient and environmental-friendly as compared to the fusion welding. Despite several advantages of FSW over fusion welding, the thermal cycles involved in FSW cause softening in joints generally in heat-treatable aluminum alloys (AAs) due to the dissolution or coarsening of the strengthening precipitates leading to decrease in mechanical properties. Underwater friction stir welding (UFSW) can be a process of choice to overcome these limitations. This process is suitable for alloys that are sensitive to heating during the welding and is widely used for heat-treatable AAs. The purpose of this article is to provide comprehensive literature review on current status and development of UFSW and its importance in comparison to FSW with an aim to discuss and summarize different aspects of UFSW. Specific attention is given to basic principle including material flow, temperature generation, process parameters, microstructure and mechanical properties. From the review, it is concluded that UFSW is an improved method compared with FSW for improving joint strength. Academicians, researchers and practitioners would be benefitted from this article as it compiles significantly important knowledge pertaining to UFSW. 相似文献
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《Science & Technology of Welding & Joining》2013,18(6):518-524
AbstractIn this paper, the material behaviour and mechanical characteristics of lap joint friction stir welding (FSW) between dissimilar alloys, namely, Cu and Al, is investigated. In order to produce welds of a higher quality, a layer of Cu is anodised on the aluminium alloy. The mechanical and the microstructural characterisations are performed on the welds, which are produced using various welding parameters. Scanning electron microscope with energy dispersive X-ray spectroscopy is used to identify the elemental compositions of phases that are formed. The results reveal that the use of the copper anodised layer prevented formation of brittle intermetallic compounds due to the direct FSW of 6061 aluminium alloy to copper and, as a result, enhanced the weld metallurgical and mechanical properties. 相似文献
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M. Tagami 《Welding International》2013,27(2):77-81
Friction stir welding (FSW) succeeded in producing high quality dissimilar welds with AA5083 and A6N01 by evaluation of the microstructure and the root bend testing. A6N01 with a wide optimum range of welding condition should be placed on the retreating side to weld a sound joint between AA5083 and A6N01. The optimum welding condition of FSW for the dissimilar alloys between AA5083 and A6N01 was wider than that of AA5083. In the opposite orientation, A6N01 on the advancing side can hardly flow into AA5083 on the retreating side in front of the tool. As the pores on inappropriate welding conditions were observed, large pores on a lower tool rotation speed were different from small discontinuous pores on a higher tool rotation speed. 相似文献
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搅拌摩擦焊是一种新型的塑化连接工艺,对于用熔化焊方法难于焊接的有色金属,有着极大的应用潜力。本文针对我国航空航天工业中常用的MB8镁合金,试验研究了镁合金薄板的搅拌摩擦焊工艺,对焊缝的成形特点、接头组织特征及力学性能进行了分析探讨。结果表明,MB8镁合金塑化连接的接头外观成形良好,内部无气孔、裂纹,焊后焊件几乎无变形,接头性能可达到母材抗拉强度的76%。塑化连接接头由焊核和热影响区组成,焊核区是经历了动态再结晶的细小晶粒,热影响区的晶粒较粗大。 相似文献
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S.X. Lu J. C. Yan W.G. Li S. Q. Yang 《金属学报(英文版)》2005,18(4):552-556
The thermal model of FSW based on the thermal elastic-plastic finite element method, and the transient temperature distribution of FS welded joints of 2024-T4 Al was simulated by using this model, which provides useful information for the investigation of FSW process. Simulation resuits show that the temperature distribution of the weld gradually decreases toward periphery in a radiate format, whose center is the probe, and the highest temperature in the weld can reach about 400℃. The initial terminal of the weld is a zone, in which the temperature gradient is great, and defects of the welding are easily produced in this zone. Temperature change at the end of the welded joint is as layer variation, the local serious defects are not easy to produce in this zone. 相似文献
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There is high demand for lightweight but strong materials, which has brought about hybrid structures that are made from dissimilar light materials such as aluminium alloys. Friction stir welding (FSW) can be used not only for the joining of dissimilar materials but to produce structures with enhanced properties by incorporating reinforcing fillers (e.g., SiC) into the weld. The quality of welds produced using FSW can be affected by imperfect welding process parameters or uncontrollable variables. The objective of this work was the application and verification of a high-frequency ultrasonic technique for the investigation of dissimilar metal joint quality. Four welds with different numbers of friction stir processing passes were investigated using macroscopic study, acoustic microscopy (AM), and X-ray computed tomography (CT) techniques. Image fusion of the AM and CT results are presented, and these confirm the images obtained with the acoustic microscope correlate well with the X-ray CT. Investigations demonstrate that scanning acoustic microscopy can show even the smallest voids, their position, and their size in the weld. It was shown that number and the direction of passes influence the quality of the weld considerably. The presented results prove that the macrostructural study is not sufficient to evaluate the quality of the friction stir weld. 相似文献