Satish Kumar T, Thankachan Titus, Čep Robert, Kalita Kanak
Department of Mechanical Engineering, Amrita School of Engineering, Amrita Vishwa Vidyapeetham, Coimbatore, 641112, India.
Department of Mechanical Engineering, Karpagam College of Engineering, Coimbatore, India.
Sci Rep. 2024 Nov 4;14(1):26686. doi: 10.1038/s41598-024-77814-8.
In this study, the effect of ultrasonic vibration during Friction Stir Vibration Processing (FSVP) on the microstructure and mechanical behaviour of AZ31/TiC surface composites was investigated. Specifically, Titanium Carbide (TiC) particles were introduced as a reinforcement (15 vol%) into the magnesium alloy AZ31 using both Friction Stir Processing (FSP) and FSVP. Comprehensive examinations were carried out to analyse the microstructure, hardness, and tensile behaviour of the resulting composites. The study revealed significant improvements in mechanical properties due to the application of ultrasonic vibration during FSP. Firstly, the stir zone region was found to be free from voids, enhancing material flow and promoting even dispersion of TiC powders within the matrix. Secondly, refinement of grains was observed due to dynamic recrystallization and the pinning effect imposed by TiC particles, leading to the formation of more dislocations in the composite and indicating a considerable alteration in the material's structure. Importantly, the vibration during FSP introduced an auxiliary energy source, resulting in a remarkable enhancement in both hardness and tensile strength. Compared to the AZ31/15 vol% TiC FSP composite, the composites produced via FSVP exhibited a grain size reduction of about 64% and improvements in hardness and ultimate tensile strength (UTS) of about 55% and 21%, respectively. Notably, these improvements were achieved without compromising the ductility of the composite, which remained at appreciable levels.
在本研究中，对搅拌摩擦振动加工（FSVP）过程中的超声振动对AZ31/TiC表面复合材料微观结构和力学行为的影响进行了研究。具体而言，使用搅拌摩擦加工（FSP）和FSVP两种方法，将碳化钛（TiC）颗粒作为增强相（15体积%）引入镁合金AZ31中。对所得复合材料的微观结构、硬度和拉伸行为进行了全面检测。研究表明，由于在FSP过程中施加了超声振动，复合材料的力学性能有显著改善。首先，发现搅拌区无孔隙，增强了材料流动并促进了TiC粉末在基体中的均匀分散。其次，由于动态再结晶以及TiC颗粒产生的钉扎效应，观察到晶粒细化，导致复合材料中形成更多位错，表明材料结构发生了显著变化。重要的是，FSP过程中的振动引入了辅助能源，导致硬度和拉伸强度均显著提高。与AZ31/15体积%TiC FSP复合材料相比，通过FSVP制备的复合材料晶粒尺寸减小了约64%，硬度和极限抗拉强度（UTS）分别提高了约55%和21%。值得注意的是，在不降低复合材料延展性的情况下实现了这些改善，复合材料的延展性仍保持在可观水平。
