Improving mechanical properties of composite/metal friction stir lap welding joints via a taper-screwed pin with triple facets

摘要

Material flow rates at the horizontal and vertical directions were markedly increased by a taper-screwed pin with triple facets. A stationary shoulder could prevent plasticized materials overflowing out of the weld and make them backflow into the nugget zone, achieving good surface integrity. The short carbon fiber-reinforced polyether-ether-ketone and the AA2060-T8 were tightly joined, and the carbon fibers were dispersedly distributed at the nugget zone, which attributed to the effective load transfer effects and then improved the joint strength. The tensile shear strength reached 18 MPa. The combination of the stationary shoulder tool system and plunging the taper-screwed pin with triple facets into the composite was feasible and effective to improving mechanical properties of composite/metal friction stir lap welding joints.