Friction stir additive manufacturing of AZ31B magnesium alloys via off-axis delivery and coaxial deposition

A novel friction stir additive manufacturing technique was proposed for magnesium alloys, integrating segmented rod feedstock and a dedicated rod loading module enabling continuous material off-axis delivery and coaxial deposition. A defect-free AZ31B magnesium alloy component was fabricated with a high building rate of 2.0 kg/h. Deposited layers featured a homogeneous grain structure, with an average grain size of 7.49 ± 0.21 μm. The ultimate tensile strength and elongation in both the traveling direction and building direction exceeded 230 MPa and 7.0%. This work offers further progress in the high-efficiency solid-state additive manufacturing of magnesium alloys.