Comparative Study on Distortions in available Residual Stress Specimens of PBF-LB/M Manufactured Ti6Al4V.

Residual stresses pose a significant challenge in additive manufacturing as they lead to distortions, making measurement processes complex and resource-intensive. Existing methods often face limitations, while practical approaches rely on specimens to estimate these distortions. Given the diversity of available specimen designs, their suitability for accurate measurement and simulation requires further evaluation. This paper addresses these challenges and provides a comparative study of various specimen geometries from the literature for distortion assessment caused by residual stresses. The focus is on evaluating measurement accuracy and the influence of different specimen dimensions as well as manufacturing process stability. To achieve this, different simulations, experiments, and measurements on printed specimens were conducted to systematically compare the effectiveness of different designs. The results present an improved specimen design tailored for assessing distortions induced by residual stresses, combined with offering a structured overview of existing designs, their advantages, limitations, and the impact of key factors.