Modeling offers great potential for reducing experimental effort in development of welding parameters, tool design and many other areas and at the same time reduce cost and time. An analytical model for heat generation for friction stir welding using taper cylindrical pin profile was developed. The proposed analytical expression is the modification of previous analytical models known from the literature which is verified and well matches with the model developed by previous researchers. The results of the proposed model were validated with the data from previous researchers. From the obtained results, it was observed that less temperature is generated using taper cylindrical pin profile than straight cylindrical pin profile under given set of working conditions. Furthermore, numerical simulation result shows that increasing the taper pin angle leads to decrease in peak temperature

In this study, friction stir welding window for AA6061-T6 aluminium alloy based on tool rotational speed and weld speed was developed. The formation of friction stir welding/processing zone has been analysed macroscopically and microscopically. Fracture locations of the joints were also analysed using scanning electron microscope. It has been experimentally found that the joint fabricated using tool rotational speed of 1000 r/min and weld speed of 40 mm/min (obtained from friction stir welding window), tool shoulder diameter of 24 mm with tapered cylindrical pin profile and the ratio of shoulder to pin diameter with value 3 showed better mechanical properties compared to other joints. The developed welding window will be used as ready reckoner to select appropriate rotational and welding speed to fabricate defect-free joints.

The dissimilar material joining of aluminum and titanium alloys is recognized as a challenge due to the significant differences in the physical, chemical, and metallurgical properties of these alloys, where the increasing demands for high strength and lightweight alloys in aerospace, defense, and automotive industries. Joining these two alloys using the conventional fusion techniques produces commercially unacceptable sound joints due to irregular, complex weld pool shapes, cracking and low strength, high residual stresses, cracks, and microporosity, and the brittle intermetallic compounds formation leads to poor formability or inferior mechanical properties. The formation of intermetallic compounds is inevitable but it is less severe in solid-state than in the fusion welding process. Hence, this article reviews on aluminum–titanium joining using different solid-state and hybrid joining processes with emphasis on the effect of process parameters of the different processes on the weld microstructure, mechanical properties along with the type of intermetallic compounds and defects formed at the weld interface. Among the various solid-state welding processes for aluminum–titanium joining, the following grades of aluminum and titanium alloys were employed such as cp Ti, Ti6Al4V, cp Al, AA1xxx, AA 2xxx, AA5xxx, AA6xxx, AA7xxx, out of which Ti6Al4V and AA6xxx alloys are the most common combination.