Emphasizing the Effects of Tool Geometry on Surface Modification of Aluminium 6063 by Friction Stir Processing

Aluminium alloy 6063 has a wide application in special machine elements, architectural sections,
automobiles and frame systems. AA6063 has high strength to weight ratio but low hardness and wear
resistance property. Friction Stir Processing (FSP) is a surface modification process through which
mechanical properties of the surface can be improved by reinforcing ceramic particles. In this present
investigation, surface property of Aluminium alloy 6063 is modified by reinforcing Boron Carbide (B4C)
powder particles via FSP. The distribution of B4C particles were examined for different reinforcing
techniques, based on Hardness and Impact strength, by keeping volume fraction (22.38%) constant.
The tool pin profiles such as threaded cylindrical and square pin were also compared for the best
distribution of B4C in the surface of base metal through different reinforcing techniques. The tool
rotational speed 1200 rpm, travel speed 40 mm/min and axial force 10 kN are kept constant.
Friction stir processing is an effective method to improve hardness by reinforcing Boron carbide
particles into the base metal surface. The maximum hardness and impact strength is achieved, when
the B4C particles are packed into the serial holes and friction stir processed with square pin profile
tool. Increased hardness in the Stir zone shows the uniform distribution of B4C particles. Thus
serial holes reinforcement method with square pin tool can be employed for surface modification via
FSP.