2013 Volume 7 Issue 4 Pages 507-519
This paper describes about the joint strength and their improvement of a type 5052 aluminum alloy (A5052) autocompleting friction welded joint, that welding method was developed by authors. When the joint was made at a friction pressure of 60 MPa, it had approximately 75% joint efficiency at a groove bottom thickness of 1.1 mm with an overhanging length of the weld faying surface part (overhanging length) for the fixed workpieces of 15 mm. Those joints had the flexural deformation of the fixed workpiece during the welding, although those had the circumferential shear fracture by the increasing insert thickness with reliability. To reduce the flexural deformation of the fixed workpiece, the joint was made with an overhanging length for the fixed workpieces of 5.0 mm. The joint had 100% joint efficiency with the base metal fracture at a groove bottom thickness of 1.4 mm which was made at a friction pressure of 80 MPa, although that did not achieve 100% joint efficiency at a friction pressure of 60 MPa. In addition, the joint with a groove bottom thickness of 1.3 mm or thin did not achieve 100% joint efficiency, and that with 1.5 mm or thick did not have the circumferential shear fracture. To obtain the generating of the circumferential shear fracture with reliability during the friction process and 100% joint efficiency with the base metal fracture, the joint should be made with thick insert piece, opportune groove bottom thickness of the insert piece, short overhanging length for the fixed workpieces, and relatively high friction pressure.
