The present research fabricated a dissimilar friction stir welded joints of AA6161 and AA5083 by incorporating Nano-sized Al₂O₃ nanoparticles. The effect of multipass friction stir welding (FSW) on the dispersion pattern of Al₂O₃ nanoparticles and the impact of particles’ dispersion on microstructure and various mechanical characteristics was investigated. The results demonstrated that multi-pass FSW had significant impacts on the Al₂O₃ nanoparticles’ distribution. Furthermore, the dispersion pattern of Al₂O₃ nanoparticles in the stir zone strongly influenced the microstructure and mechanical characteristics. The results obtained from mechanical testing after a microstructural study corroborate multi-pass FSW. Tensile strength, strain rate, and micro-hardness of the Al₂O₃ reinforced joints of AA6061/AA5083 were improved after implementing multi-pass FSW. The improvement in the mechanical characteristics was observed via higher grain refinement by pinning effect and dynamic recrystallization by Al₂O₃ nanoparticles. The tensile strength after one, two and three FSW passes were observed to be 227.3, 257.4 and 272.7 MPa, with a % strain of 24.4, 26.8 and 30.7, respectively. Furthermore, the hardness value after 1 pass, 2 pass, and 3 pass FSW were 127.1, 136.4 and 145.7 HV, respectively.

本研究通过掺入纳米级Al ₂ O ₃纳米粒子制造了AA6161 和AA5083 的异种搅拌摩擦焊接接头。研究了多道次搅拌摩擦焊（FSW）对Al ₂ O ₃纳米颗粒分散模式的影响以及颗粒分散对微观结构和各种力学特性的影响。结果表明，多道FSW对Al ₂ O ₃纳米粒子的分布有显着影响。此外，Al ₂ O _{3的分散模式}搅拌区中的纳米颗粒强烈影响微观结构和机械特性。在微观结构研究之后从机械测试获得的结果证实了多通道 FSW。实施多道次FSW后，AA6061/AA5083的Al ₂ O ₃增强接头的抗拉强度、应变率和显微硬度得到改善。通过钉扎效应的更高晶粒细化和 Al ₂ O _{3的动态再结晶观察到机械特性的改善}纳米粒子。观察到一、二和三遍 FSW 后的拉伸强度分别为 227.3、257.4 和 272.7 MPa，应变百分比分别为 24.4、26.8 和 30.7。此外，1 道、2 道和 3 道 FSW 后的硬度值分别为 127.1、136.4 和 145.7 HV。