Effect of Al₂TiO₅ Particle on the Temperature Distribution of Friction Stir Welded Dissimilar Aluminium Composites Using Response Surface Methodology

The present study investigates the peak temperature and temperature distribution of dissimilar friction stir welded (DFSW) AA5052-Al₂TiO₅/AA6061-Al₂TiO₅ composites. The weight percentage (wt.%) of the synthesized Tialite (Al₂TiO₅) particles, tool rotational speed, feed rate, and thermal conductivity (TC) of the composites are considered for this study. The TC of the composites is measured using a KD2 pro decagon devices instrument, and the theoretical TC is calculated by parallel model equation. The peak temperature of DFSW joints is investigated using a central composite design of experiments with three input parameters, namely TRS, feed rate, and wt.% of reinforcements. The results show that the TC of composites decreases with increasing Al₂TiO₅ wt.%. The maximum peak temperature of 474 °C is obtained for 1400 rpm TRS, 30 mm/min feed rate, and 1 wt.% (W13). The minimum peak temperature of 377 °C is obtained for 1000 rpm TRS, 50 mm/min feed rate, and a 3 wt.% Al₂TiO₅ (W2). The structural analysis reveals that the samples W5, W10, W11, W12, and W15 exhibit defect-free DFSW joints with peak temperatures ranging from 447 °C to 452 °C. Additionally, X-ray diffraction analysis confirms the presence of Al₂TiO₅ particles in the DFSW stir zone, and the phase intensity variation confirms that mono-synthesized Al₂TiO₅ wt.% and TRS play a significant role in temperature distribution and peak temperature of DFSW joints.