Abstract
This paper presents an investigation on the performance of rotary friction welded 25.4
mm diameter Ti-6Al-4V alloy rods. The process parameters used are friction and forging
pressure, rotational speed, forging time and upset distance. The heating time was determined by
the amount of friction pressure and rotational speed utilised. The final weld joints were examined
for mechanical properties. The results revealed that friction welding process parameters have
significant influence on the weld joint properties and weld joint integrity. The hardness and
ultimate tensile properties of the weld joints varied with the variation in rotational speed and
axial pressure. The tensile properties of the weld joints were higher than the parent material at
lower rotational speed or higher axial pressure. The weld width was proportional to relative
motion and inversely proportional to axial pressure.