6533b7dcfe1ef96bd127292c

RESEARCH PRODUCT

In-process tool force and rotation variation to control sheet thickness change in friction stir welding of magnesium alloys

Gianluca BuffaMichela SimonciniLivan FratiniArchimede Forcellese

subject

Physics and Astronomy (all)Materials sciencelawMetallurgyUltimate tensile strengthFormabilityFriction stir weldingRotational speedWeldingFriction weldingMagnesium alloyElectric resistance weldinglaw.invention

description

Two different in-process control strategies, developed in order to produce sound joints in AZ31 magnesium alloy by Friction Stir Welding on sheet blanks with a non-uniform thickness, are presented and compared. To this purpose, sheets with dip or hump were machined and welded by either changing the rotational speed or the tool plunging in order to keep constant the vertical force occurring during welding. The mechanical strength of the joints was measured in the zones where the sheets before welding were characterised by different thicknesses. The sheets welded by the two different strategies are characterized by very similar ultimate tensile strength values. Finally, the results showed that the two approaches permit to successfully weld sheets with non-uniform thickness with a reduced loss in the mechanical strength.

10.1063/1.4963502http://hdl.handle.net/10447/212153