Microstructures and performance of welded joints of red copper and brass by friction stir welding

摘要

The friction stir welding of red copper and brass were carried out at a serious of welding parameters. The properties and microstructures of the welded joints were analyzed. Tensile and bending test results indicate that the welded joints can achieve good combination of strength and ductility at rotation speed of 950rpm, welding speed of 60 mm/min and Z-axis force of 2000N. The tensile specimen failed at the base material of red copper. The weld nugget zone has very fine dynamic recrystallization microstructure and its Vickers hardness falls in between those of the two base metals. The sharp interface between the TMAZ and nugget might result in brittle fracture.