Evaluation of in situ hot-rolling forming effect on plastic zone of wire + arc additively manufactured 5087 alloys using digital image correlation technique

Abstract

The fatigue crack growth (FCG) rates and crack-tip plastic zone size data for wire + arc additive manufacturing (WAAM)-processed 5087 alloys before and after in situ hot-rolling treatment were investigated and compared. After hot-rolling, the WAAM-processed alloys possessed higher strength. During the FCG tests, the crack-tip field was monitored using a digital image correlation (DIC) technique. The improved FCG resistance and smaller plastic zone area of the WAAM-processed alloys after hot-rolling were responsible for the grain refinement. Therefore, in situ hot-rolling treatment is a promising technique for optimising the properties of WAAM-processed alloys.