Abstract
Effects of brake timing on the mechanical properties of welded joints of 5052 aluminum alloy, which were made by using a numerical controlled brake type friction welding machine, were investigated. The total loss of welded joint became shorter with decrease of brake timing. The highest tensile strength of welded joint was 240.8 MPa, joint efficiency was 93.2%, at brake timing of 0 second. The tensile strength of welded joints under conditions of brake timing from -0.1 to 0.2 seconds showed almost same value, and they were fractured at the heat affected zone. The highest elongation of welded joint was obtained when braking time 0.2 seconds. The welded joints, exceed the elongation of 14%, were fractured at the soften area. But welded joints, elongation under 5%, were fractured at the weld interface.
