Speaker
Description
Mechanical property verification for laser powder bed fused (LPBF) Ti-6Al-4V traditionally relies on machined witness specimens and destructive tensile testing. Indentation plastometry offers a faster, less material-intensive alternative by extracting stress-strain behaviour from controlled surface deformations via inverse numerical analysis. However, implementing this methodology for additive manufacturing quality assurance requires low prediction error, minimal systematic bias, and robust repeatability across diverse microstructural states.
This study evaluates the predictive capability of the Imprintec indentation-plastometry system against conventional tensile testing, comparing its original analysis routine with a vendor-revised, bias-corrected algorithm. A comprehensive dataset of 96 cylindrical specimens was produced across 24 combinations of LPBF processing parameters, heat-treatment conditions, and hot isostatic pressing (HIP) routes (four replicates per condition). Each specimen was sectioned to ensure that indentation plastometry and uniaxial tensile testing were conducted on material with identical processing and thermal histories.
Initial evaluation using the original analysis routine successfully captured qualitative trends in yield strength and ultimate tensile strength, but revealed notable systematic under prediction, while elongation estimates showed limited quantitative agreement. These observations led to the implementation of a revised bias correction. Both routines were subsequently applied across the complete dataset to evaluate changes in prediction accuracy, systematic bias, repeatability, and condition-dependent performance using linear trend analysis, mean absolute error (MAE), root-mean-square error (RMSE), and Bland-Altman agreement analysis. Subgroup analyses were also performed to assess sensitivity to specific heat-treatment and HIP routes.
The results establish the extent to which the bias-corrected Imprintec routine reduces systematic error and enhances quantitative strength predictions within the LPBF Ti-6Al-4V process window. Finally, the study highlights the distinct physical challenges of predicting localized ductility and defines the overall viability of indentation plastometry for rapid quality screening, trend monitoring, and reducing destructive testing requirements in additive manufacturing.
Keywords: laser powder bed fusion; Ti-6Al-4V; Imprintec; indentation plastometry; tensile testing; mechanical property prediction; quality assurance
This study aligns directly with the scope of MAMC 2026, and I am confident it will offer meaningful insights to the conference audience.
| Speaker Country | Germany |
|---|---|
| Would you like to publish your paper in the special issue of BHM "Berg- und Hüttenmännische Monatshefte" | Yes |