Material Flow in Lap Joint of Dissimilar Metallic Foils by Friction Stir Diffusion Bonding with Micro Indentation

Abstract:

Friction stir diffusion bonding (FSDB) has been applied to lap dissimilar foils joints of aluminum alloy on top of commercial purity (CP) titanium. FSDB of the foils was successfully performed through stirring only the upper aluminum foil by the air spindle with an extremely-high rotation speed of 105,000 rpm. By using smooth surface of the tool tip, FSDB with micro indentation less than or equal 10μm could be carried out to improve the surface condition of the joint and the indentation depth required for joining was reduced. The material flow of the upper aluminum alloy foil in the FSDB was investigated by deposited platinum-palladium as the tracer material on the surface of the lower titanium foil. Then it was confirmed that the vestiges of vigorous stirring appeared in the region given at a distance from tool center while little vestiges was found in the other region. These regions seemed to be bounded by a radius of about 0.6 mm from the tool center. Moreover, the bonding strength distribution as a function of the distance from the tool center was likely correspondent to the stirring state.

• Periodical: Materials Science Forum (Volume 941)
• Pages: 1450-1456
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.941.1450
• Online since: December 2018
• Authors: Takashi Kodama*, Hiroki Fukushige, Kouhei Igari, Kazuki Nakayama, Yoshimasa Takayama
• Keywords: Aluminium Alloy, Dissimilar Materials Bonding, Friction Stir Welding, Material Flow, Titanium

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