Abstract

The objective of the present study is to investigate the effect of Al₂O₃ nanoparticles volume percentage on tribological, mechanical and microstructural characteristics of 6061-T6 aluminum alloy based particulate-nanocomposite (P-NCs) fabricated using friction stir welding (FSW) process. Optical microscopy (OM) and scanning electron microscopy (SEM) was employed to evaluate the (a) microstructures of the produced nanocomposites to ascertain the distribution of Al₂O₃ nanoparticles in the nugget zone; (b) nanocomposite depth formed on Al-alloy matrix, and (c) fractured and wear characteristics. Results reveal that the produced P-NCs had a depth of 3286 µm across the perpendicular x-section of the weld nugget zone of P-NCs. With the increase in a volume percentage of Al₂O₃ nanoparticles there was a tremendous increment in the microhardness up to 125 HV which is higher than as-received AA6061-T6. It was also noticed that the tensile strength and the wear resistance of produced P-NCs were significantly increased at 0.3 vol% of Al₂O₃ nanoparticles as compared to 0.2 and 0.4 vol%. The corresponding mechanical and wear properties results were correlated to microstructure and fractography results.

摘要

本研究的目的是研究Al ₂ O ₃纳米颗粒的体积百分率对使用摩擦搅拌焊接（FSW）工艺制备的6061-T6铝合金颗粒-纳米复合材料（P-NCs）的摩擦学，力学和微观结构特征的影响。 。使用光学显微镜（OM）和扫描电子显微镜（SEM）评估所产生的纳米复合材料的（a）微观结构，以确定Al ₂ O ₃的分布熔核区中的纳米颗粒；（b）在铝合金基体上形成的纳米复合材料深度，以及（c）断裂和磨损特性。结果显示，所生产的P-NC在P-NC焊缝熔核区的垂直x截面上的深度为3286 µm。随着Al ₂ O ₃纳米颗粒的体积百分比的增加，高达125 HV的显微硬度有了极大的提高，这比预期的AA6061-T6高。还注意到，与0.2和0.4体积％相比，在0.3体积％的Al ₂ O ₃纳米颗粒时，制得的P-NC的拉伸强度和耐磨性显着提高。相应的机械和磨损性能结果与显微组织和断口扫描结果相关。