Effects of Tool Rotation Speed and Pin Geometry on Properties in Friction Stir Welding of Brass

Abstract

In this study, CuZn37 brass sheets were joined by applying three different stirrer pins and different tool rotation speeds of 500, 800, and 1100 rpm by friction stir welding, while tool travel speed (40 mm.min(-1)), and other parameters were kept constant. Effects of the used weld parameters were investigated in weld zone and mechanical features via tensile test, microhardness measurement and optical and scanning electron microscopies. The rising of temperature in stir zone was also measured by using K-type thermocouple. The tensile test results show that a defect-free joint having weld performance of 81% of the base brass metal was achieved by using a conical pin without flattened at tool rotation speed of 800 rpm. The stir zone of this joint slightly softened according to the base metal and the heat-affected zones showed the lowest hardness values. The peak temperature in the stir zones was increased with increasing of tool rotation speed, consequently arrived to 804 degrees C at 1100 rpm.