Metallographic Characterization of Friction Stir Channels

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Abstract:

Friction Stir Channelling (FSC) is an innovative technique of manufacturing integral and continuous channels (also referred as conformal channels) in monolithic plates in a single step. The process is capable of producing non-linear channels in solid components with similar control of the parameters applied during Friction Stir Welding. The tool geometry and concept plays a major influence in the results from FSC. During FSC a controlled amount of workpiece material flow-out from the processed zone producing the internal channel. The heat energy that softens the workpiece material is generated from dissipation during plastic deformation, internal viscous dissipation during the material flow and dissipation from frictional work between the tool and the workpiece. This research work is based on a detail metallographic, geometric and hardness analysis of integral and continuous FS channels produced in a monolithic plate of the aluminium alloy AA7178‑T6 with 13mm of thickness, typically used in structural aircraft applications. In this paper the metallographic characterization and the hardness distribution in the processing zone that surrounds the channel are presented and discussed. Channel’s geometric characterization is also presented and discussed. The channel microstructure and its roughness features were obtained using optical microscopy and SEM.

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Periodical:

Materials Science Forum (Volumes 730-732)

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817-822

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Online since:

November 2012

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