The Effect of Scanning Strategies on FeCrAl Nuclear Thin-Wall Cladding Manufacturing Accuracy by Laser Powder Bed Fusion

Abstract

FeCrAl alloy has been proposed as an alternative material for accident-tolerant fuel (ATF) cladding for nuclear reactors. Thin-wall cladding can be rapidly fabricated by laser powder bed fusion (LPBF). In this paper, a finite element model is established to simulate the transient temperature fields of the cladding under two different laser scanning strategies (linear scanning and ring scanning). In linear scanning simulations, bidirectional scanning, compared with unidirectional scanning, had a smaller temperature gradient along the radial direction. In the ring scanning simulation, the maximum temperature gradually increased and then became stable with the increase of layers. Then, FeCrAl thin-wall cladding with a wall thickness of 0.14 mm was fabricated by LPBF. FeCrAl cladding using the ring scanning strategy had a smaller roughness value (Ra = 4.061 μm). Ring scanning had better accuracy than bidirectional scanning for FeCrAl thin-wall cladding with a wall thickness below 0.4 mm. Therefore, compared with the bidirectional scanning, the ring scanning is more suitable for the high-accuracy manufacturing of FeCrAl thin-wall cladding.