Effects of inclination angle of faying surface on the mechanical properties of friction welded joints of 5052 aluminum alloy.

Effect of inclination of faying surface on the mechanical properties of 5052 aluminum alloy joints, which were welded by a brake type friction welding machine, has been investigated. The inclination angle of faying surface to the specimen axis was 0° to 25°. The axial shortening increases at first rapidly and then slowly with increase in the welding time. It is found that the initial axial shortening speed increases with increasing the inclination angle. Regardless of the friction time, both burn off length and total loss increased with increasing inclination angle. Heat affected zone of welded joints became narrower with increasing inclination of faying surface. The inclination of faying surface had no effects on the microstructures of joint. Hardness of weld zone was lower than that of the base metal. The width of softening zone tended to decrease with increase in the inclination angle. Tensile strength of the welded joints was 84% as large as that of the base metal independent of the inclinatin angle of faying surface. Regardless of both welding condition and inclination of faying surface, the elongation of welded joints was 81% as large as that of the base metal. All joints fractured at the heat affected zone.