Purpose: The purpose of this thesis work is to evaluate the feasibility of producing similar joints of AA6005 extruded aluminium alloy and dissimilar joints of AA6005 extruded aluminium alloy and AC 43500 aluminium casting by using friction stir welding as well as to investigate the mechanical properties of the friction stir welds with varying process parameters, speed optimization and the development of workable process parameters of the base materials for industrial use.

Design/methodology/approach: The friction stir welded joints were produced using ESAB Rosio, a FSW robotic equipment with temperature control systems and tool-work-piece-thermocouple used for temperature measurement. Mechanical testing such as hardness, tensile and bending test was carried out and correlation with the process parameters was investigated. Optical microscopy (OM) was used to evaluate the joint macrostructure.

Results: Workable process parameters were successfully achieved for the proposed base materials with the joints exhibiting good mechanical properties and joint efficiency within the accepted criteria according to ISO 25239. Good material mixing was also observed in the FSW joint macrostructure. Joint line remnant (JRL) which is classified as a feature in FSW joints was found and analysed in similar joints. Wider heat-affected zone (HAZ) was observed in the joints produced at lower welding speed compared to the joints produced at higher welding speed.

Implications: Producing FSW joints at higher welding speed or optimized process parameters will be beneficial to cost reduction and increased efficiency of the operation.

Value: The results of this thesis work can be used as a basis for weld procedure development on industrial applications. Useful for further studies to investigate the feasibility of producing joints at higher welding speed with good joint properties. Also, improve the efficiency of the process.