Study of residual stresses and distortions from the Ti6Al4V based thin-walled geometries built using LPBF process

Abstract

The current paper focuses on the prediction of residual stresses and distortions in the Laser Powder Bed Fusion (LPBF) built Ti6Al4V thin-walled geometries using Ansys Additive Print (AAP) software which employs a layer-by-layer accumulation of inherent strain to calculate the deformations. Isotropic and anisotropic strain scaling factors were calibrated initially within the APP software for the Ti6Al4V based single cantilever beam geometry. Subsequently, the numerical simulations were performed in APP software and computed the residual stresses and distortions for the varied process parameters including laser power, scan speed and hatch distance while maintaining the layer thickness constant for all the design iterations. The numerical predictions were compared; they were found to match reasonably well with the XRD measurements within the calibrated regime.

Keywords

• Ti6Al4V
• Thin-walled geometry
• Residual stress
• Inherent strain
• XRD
• Ansys additive print