Friction-stir lap-joining of aluminium-magnesium/poly-methyl-methacrylate hybrid structures: thermo-mechanical modelling and experimental feasibility study

ABSTRACT

In this research, the feasibility of friction-stir welding (FSW) for dissimilar lap-joining of an aluminium-magnesium alloy (AA5058) and poly-methyl-methacrylate sheets to attain sound and defect-free joints was examined. The inter-mixing flow patterns between the metal and polymer counterparts during FSW were predicted by employing three-dimensional finite element models. It is shown that the bonding mechanism between the dissimilar materials is mechanical interlocking at the interface which controls the joint strength depending on the processing parameters. The most suitable dissimilar lap-joining regarding microstructural soundness is attained at w= 1600 rev min⁻¹ and v = 25 mm min⁻¹. Under this condition, the maximum joint strength, which is about ∼60% of the weakest base material, is attained. Fractography indicates that the rupture occurs from the aluminium side.

KEYWORDS:

• Dissimilar joining
• friction-stir welding
• PMMA
• aluminium alloy
• thermo-mechanical modelling
• microstructure
• mechanical property

Disclosure statement

No potential conflict of interest was reported by the authors.