Study of the Surface Nanocrystallization Induced by the Esonix Ultrasonic Impact Treatment on the Near-Surface of 2024-T351 Aluminum Alloy

摘要

A nanocrystalline surface layer of Al alloy induced by the Esonix Ultrasonic Impact Treatment process was studied by advanced electron microscopes. The results revealed that the process can effectively refine the surface coarse grains into equiaxed nanocrystalline grains (grain size: 8.0-10.0 nm) and elongated micro-bands (15-20 nm wide). The surface affected zone was measured to be approximately 10 mu m. The micro-structural features include nanograins, microbands, high-density dislocation, and twining structure.