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DOE OSTI · 2998912

Cladding and Butt-Joining Dissimilar Aluminum Alloys Simultaneously via Shear Assisted Processing and Extrusion

Milligan, Brian K.·Li, Lei·Komarasamy, Mageshwari·Roosendaal, Timothy J.·Soulami, Ayoub·Whalen, Scott A.
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Abstract

Shear assisted processing and extrusion has been used to fabricate multi-metallic tubing that incorporates regions with clad and butt-joined structures. In this work, aluminum alloys 6061, 7075, and 1100 are combined to create a monolithic extruded tubing with weldable ends (6061), a high strength center (7075), and a corrosion-resistant cladding (1100). Optical microscopy shows a gradual, defect-free, transition between alloys at the butt-joint interfaces and a sharp transition between alloys at the clad interface. Tensile testing proved the mechanical coherency of the joint, with failure occurring outside the tri-metallic structure. In conclusion, smoothed particle hydrodynamic simulations identified a spiral pattern of the cladding alloy that leads to inconsistent cladding thickness, and identified a simplified 2-alloy combination of aluminum alloys 6082 and 2014 that accomplished the design objectives of the tri-metallic structure.

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Milligan, Brian K., Li, Lei, Komarasamy, Mageshwari, Roosendaal, Timothy J., Soulami, Ayoub, Whalen, Scott A.. 2023-05-09. Cladding and Butt-Joining Dissimilar Aluminum Alloys Simultaneously via Shear Assisted Processing and Extrusion. https://doi.org/10.1007/s11837-023-05855-x

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