Investigation on Mechanical Properties of Disk Laser Welded Aerospace Alloys

Abstract:

The original micro structure of the base metal is significantly affected by a welding thermal cycle, irrespective of the type of the heat source. Hence, new phases and different grain size result in the welding bead. The tensile strength of the overall structure is affected in turn. Tensile tests are normally conducted to eventually test a square butt joint configuration. In conjunction, micro hardness is thought to be a good indicator to predict where the fracture would occur in the welded structure. Referring to common metal alloys for aerospace and considering a diode-pumped disk-laser source, the response of the base metal to the laser beam is investigated in this paper. Autogenous welding of aluminum alloy 2024, autogenous welding of titanium alloy Ti-6Al-4V and dissimilar welding of Haynes 188 with Inconel 718 are discussed, with respect to micro structure changes in the fused zone and in the heat affected zone. The failure mode is examined.

• Periodical: Advanced Materials Research (Volume 702)
• Pages: 128-134
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.702.128
• Online since: May 2013
• Authors: Fabrizia Caiazzo, Vittorio Alfieri, Vincenzo Sergi
• Keywords: Aluminium Alloy, Disk Laser, Laser Welding, Superalloy, Ti6Al4V

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