Fig. 2.

Micromorphology and microstructures of Ti6Al4V alloy fabricated by LWAM assisted with ultrasonic vibration: (a) and (b) are the microstructures of the Y-Z plane of zone ‘S’ and zone ‘L + S’, respectively. Corresponding, (c), and (d) are the microstructures of the X-Z plane. (e) and (f) are the microstructures of the marked area in (d). The prior-β grain boundaries are traced in red. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)