Understanding and designing post-build rolling for mitigation of residual stress and distortion in wire arc additively manufactured components

Digital Image Correlation for Measuring Full-Field Residual Stresses in Wire and Arc Additive Manufactured Components

“…Localised heating and uneven cooling during the WAAM process introduce large thermal gradients causing distortion and residual stresses, which can affect the topology and global integrity of a WAAM component [ 3 ]. In the last decade, WAAM induced residual stresses have been experimentally investigated for various alloys, such as steel [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ], aluminium [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ], titanium [ 3 , 13 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ], nickel [ 13 , 29 , 31 , 32 , 33 ], intermetallics [ 21 , 34 , 35 ], etc. The aforementioned literature has focused on quite a few areas including but not limited to the effect of process and geometrical variables on residual stresses, the effect of interpass and side rolling on controlling/reducing residual stresses, and the effect of pre-and post-processing on residual stresses, etc.…”

The Effects of the Variable-Pressure Rolling of a Wire Arc Additively Manufactured Inconel625-SS308L Bimetallic Structure

“…However, the high heat input generated during WAAM results in defects such as distortion, residual stresses, coarse columnar grains, mechanical anisotropy, pores, and thermal cracks, all attributed to the substantial heat that is generated during the process and the subsequent rapid cooling rates. To mitigate these issues, numerous studies have proposed different types of inter-layer rolling devices, demonstrating that these can reduce residual stresses, mechanical anisotropy, and transform the columnar grain structure into an equiaxed grain structure [11][12][13].…”