Microstructure and creep anisotropy of Inconel 718 alloy processed by selective laser melting

Preliminary prediction of long-term aging and creep behavior of AM 316 SS

“…The microstructure is then subjected to similar loading conditions as previous cases and as expected, the longer grains (along z) do result in a higher creep life. However, the results deviates from the experimental results in literature, such as that in [39,40], in that they do not capture any creep cavitation mechanisms that might affect the creep strength. This is owing to the fact that the CPFEM model used here does not treat grain boundaries any differently than rest of the mesh.…”

“…Ghorbanpour et al [38], for instance, studied the deformation at high temperature and looked at various loading directions with respect to build direction and attributed the plastic anisotropy to grain structure and texture. Shi et al's [39] tests had a shorter creep life when loaded perpendicular to the build direction. They attributed this anisotropy to grain boundaries being primarily distributed perpendicular to the loading direction, which could be likely regions for creep void formation.…”

Revealing the stress corrosion cracking initiation mechanism of alloy 718 prepared by laser powder bed fusion assessed by microcapillary method

“…In L-PBF processed materials, dislocation entanglement, as one of the most common line crystallographic defects, has been reported extensively at columnar/cellular subgrain boundaries [12,13,[90][91][92]. For the case of L-PBF 718, the region in the close vicinity of the subgrain boundaries was detected with a high density of dislocations due to the incoherency between the matrix and precipitated phases combined with extreme solidification cycles [12,93,94], which is also confirmed by TEM analysis, as shown previously in Fig. 5.…”

Fatigue life prediction of additively manufactured ductile nickel-based superalloys : Constitutive and crack initiation modelling

“…Other features can also be accomplished with the use of AM, such as complex internal cooling channels [7], and repairing of burner tips in gas turbines [8]. Despite all the advantages with using AM, the manufacturing technique generally leads to anisotropic material behaviour [9,10,11], i.e. different material behaviour in different directions.…”