Publications de Rafal Wróbel | EPFL Graph Search

Additively manufactured steel reinforcement for small scale reinforced concrete modeling: Tensile and bond behavior

Small scale (1:30-1:40) Reinforced Concrete is useful for centrifuge testing. However, manufacturing the reinforcing cages by hand at this scale is practically difficult. This paper suggests that small scale reinforcement can be manufactured using a metal ...

Elsevier Sci Ltd2024

Advancing efficiency and reliability in thermal analysis of laser powder-bed fusion

Christian Leinenbach, Thomas Mayer, Rafal Wróbel

In laser based powder-bed fusion of metals (PBF-LB/M), parts are fabricated by melting layers of powder using a high-intensity laser beam. During this process, the material is exposed to rapid cooling rates and intense thermal gradients, which are the unde ...

2023

Self-Supervised Bayesian representation learning of acoustic emissions from laser powder bed Fusion process for in-situ monitoring

Christian Leinenbach, Rafal Wróbel, Marc Leparoux, Sergey Shevchik

This study presents a self-supervised Bayesian Neural Network (BNN) framework using air-borne Acoustic Emission (AE) to identify different Laser Powder Bed Fusion (LPBF) process regimes such as Lack of Fusion, conduction mode, and keyhole without ground-tr ...

Elsevier Sci Ltd2023

Optimizing in-situ monitoring for laser powder bed fusion process: Deciphering acoustic emission and sensor sensitivity with explainable machine learning

Christian Leinenbach, Rafal Wróbel, Sergey Shevchik

Metal-based Laser Powder Bed Fusion (LPBF) has made fabricating intricate components easier. Yet, assessing part quality is inefficient, relying on costly Computed Tomography (CT) scans or time-consuming destructive tests. Also, intermittent inspection of ...

Elsevier Science Sa2023

Tensile and creep-rupture response of additively manufactured nickel-based superalloy CM247LC

Christian Leinenbach, Rafal Wróbel

Tensile and creep rupture properties of crack-free CM247LC alloy, processed via laser powder bed fusion, have been characterised in this work at temperatures up to 1000 & DEG;C. The subject alloy matches or even exceeds the tensile performance of its direc ...

ELSEVIER2023

Combining alloy and process modification for micro-crack mitigation in an additively manufactured Ni-base superalloy

Jamasp Jhabvala, Christian Leinenbach, Roland Logé, Xavier Maeder, Hossein Ghasemi Tabasi, Toni Ivas, Rafal Wróbel

The additive manufacturing (AM) of the gamma' precipitation strengthened Ni-base superalloys still remains a challenge due to their susceptibility to micro-cracking. Post-processing, such as HIPing, has been shown to heal the micro-cracks but it remains de ...

ELSEVIER2020