Simulation driven methodology for distortion prediction in thin-walled compressor blade built using LPBF process: Fid-Bau Portal

Simulation driven methodology for distortion prediction in thin-walled compressor blade built using LPBF process

Jagatheeshkumar, S. / Raguraman, M. / Siva Prasad, A. V. S. / Nagesha, B. K. / Chandrasekhar, U.

The present paper deals with the development of a systematic approach for predicting the distortion in thin-walled Ti6Al4V aero-engine compressor blade built using the LPBF process. Numerical simulations were conducted using Ansys Additive Print (AAP) by providing calibrated isotropic inherent strain scale factor (SSF) and anisotropic co-efficient (ASC) as input data along with the meshed part geometry. Calibration of SSF and ASC factors was performed by comparing the values between numerical and experimental measurements through a sequential iterative process considering cross-walled specimens; these specimens (two specimens in each energy density case) were built for three different energy densities: (1) Case 1—41.67 J/mm³, (2) Case 2—45.33 J/mm³ and (3) Case 3—52.78 J/mm³. Distortion of the compressor blade geometry in AAP was predicted using the calibrated input parameters. Subsequently, the identical blade geometry was built on a single base plate, adhering to the process parameters employed during the calibration study. The distortion of each of these compressor blade specimens was measured using a 3D laser scanner and compared with the numerical predictions; it was found to match with a 10% deviation. Additionally, the distortion compensation study was conducted by applying the negative distortion to the original compressor blade geometry to avoid the effects of distortion on the part quality and its relevant part failures. Hence, the current study demonstrates a practical approach for manufacturing of thin-walled Ti6Al4V components through the LPBF process with minimized and compensated part distortions.