Recent developments in concentrated energy welding processes and friction stir weldingPaper presented at the 4th National Welding Days, Workshop: “New frontiers in LASER beam welding, friction stir welding and electron beam welding processes” Genoa, 25–26 October 2007. ©TWI Ltd, 2007.

In this work, it was intended to improve the corrosion resistance of welds of A356 and AA6061 by adopting mainly a special welding techniques, viz., pulsed current gas tungsten arc welding (PCGTAW), electron beam welding (EBW) and friction stir welding (FSW). It was found that the corrosion resistance of A356 and AA6061 welds could be improved by PCGTAW technique rather than continuous current gas tungsten arc welding (CCGTAW). It can be further improved by using electron beam welding. Improved corrosion resistance in A356 welds could be obtained by selecting T6 temper rather than as cast condition. In the case of AA6061, improved corrosion resistance was achieved by selecting T4 temper rather than T6 temper. As for as the welding techniques, friction stir welding (FSW) is useful than fusion welding techniques like CCGTAW,PCGTAW and EBW for improving the corrosion resistance of both the welds.

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A Study on Different Welding Processes of IN718 for Elevated Temperature Application

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1125.186 ◽

2015 ◽

Vol 1125 ◽

pp. 186-189

Author(s):

Kyung Ju Min ◽

Jong Hoon Yoon ◽

Joon Tae Yoo ◽

Ho Sung Lee

Keyword(s):

Elevated Temperature ◽

Laser Beam ◽

Electron Beam Welding ◽

Hot Isostatic Pressing ◽

Laser Beam Welding ◽

Superplastic Forming ◽

Internal Cooling ◽

Cooling Channels ◽

Solid Solution Strengthening ◽

Welding Processes

Alloy IN718 is a nickel based precipitation hardened material and it has the necessary strength over a range of temperatures which includes the operating range for many rocket propulsion systems and jet engines. This performance is accomplished by a combination of solid-solution strengthening, precipitation strengthening and grain-boundary strengthening. However, it is common for precipitation hardened nickel based superalloys to have a problem of post-weld cracking. In this study, several welding processes are investigated to obtain the optimum welding method of IN718 for elevated temperature forming. These include LBW(Laser Beam Welding), EBW(Electron Beam Welding), HIP(hot isostatic pressing), and solid state diffusion bonding. The result shows that the LBW specimen performs the highest formability at 980°C so that this process can be applied to superplastic forming of IN718 sheet. It is demonstrated that the elevated temperature superplastic forming of nozzle extension with internal cooling channels was possible with laser beam welded IN718 sheet.

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Bifocal Hybrid Laser Beam Welding and Friction Stir Welding of Aluminium Extrusion Components

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.43.69 ◽

2008 ◽

Vol 43 ◽

pp. 69-80 ◽

Cited By ~ 6

Author(s):

Michael F. Zaeh ◽

Paul Gebhard ◽

Sonja Huber ◽

Markus Ruhstorfer

Keyword(s):

Composite Materials ◽

Friction Stir Welding ◽

Laser Beam ◽

Laser Beam Welding ◽

Welding Process ◽

Global Market ◽

Fusion Welding ◽

Critical Parameters ◽

Process Chain ◽

Friction Stir

On a global market, new products are subject to rising requirements regarding strength and quality. Simultaneously, the conservation of the environment and natural resources has become a key priority. One approach to these demands is the weight reduction of mechanical components by lightweight construction. The Transregional Collaborative Research Center (TR 10), funded by the German Research Foundation (DFG), is therefore working on the “Integration of forming, cutting and joining for the flexible production of lightweight space structures”. The use of light metals, like aluminium and composite materials is a main part in the TR10 process chain. This paper deals with the challenges of welding of light weight components made out of EN AW-6060. It shows the use and potentials of two innovative joining processes, particularly suited for welding aluminium. Especially developed for the fusion welding of aluminium components, BHLW (Bifocal Hybrid Laser Beam Welding), combines a Nd:YAG and a high power diode laser. The paper will give insight into the findings of the achieved results so far and line out the further proceedings with regard to critical parameters and their effect on the overall laser welding process. For the welding of aluminium composite materials, which play a big role in the TR10 process chain, Friction Stir Welding (FSW) is evaluated. As a solid state joining process, it can be used for the welding of materials that are hardly weldable with fusion welding techniques. In this paper, results of basic experiment for the joining of reinforced aluminium and the resulting process forces are presented.

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