Publications de Hossein Ghasemi Tabasi

Quantitative prediction of crystallization in laser powder bed fusion of a Zr-based bulk metallic glass with high oxygen content

Roland Logé, Jamasp Jhabvala, Navid Sohrabi, Hossein Ghasemi Tabasi, Toni Ivas

One of the main challenges in the fabrication of bulk metallic glasses (BMGs) via laser-based additive manufacturing (AM) is undesirable crystal phase formation, which usually deteriorates the mechanical properties of the BMG fabricated parts. Understandin ...

Elsevier Sci Ltd2024

Differentiation of materials and laser powder bed fusion processing regimes from airborne acoustic emission combined with machine learning

Roland Logé, Rita Drissi Daoudi, Hossein Ghasemi Tabasi

This study investigates the use of a low cost microphone combined with state-of-the-art machine learning (ML) algorithms as online process monitoring to differentiate various materials and process regimes of Laser-Powder Bed Fusion (LPBF). Three processing ...

TAYLOR & FRANCIS LTD2022

Understanding variant selection and texture in additively manufactured red-gold alloys

Roland Logé, Cyril Cayron, Jamasp Jhabvala, Eric Boillat, Hossein Ghasemi Tabasi

Printing gold alloys parts is a challenge due to the high reflectivity and thermal conductivity of these materials. Recent studies show an improvement in printing gold using the Laser Powder Bed Fusion (L-PBF) process; however, the impact of the A1 -> L1(0 ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Direct observation of crack formation mechanisms with operando Laser Powder Bed Fusion X-ray imaging

Roland Logé, Helena Van Swygenhoven, Jamasp Jhabvala, Eric Boillat, Navid Sohrabi, Hossein Ghasemi Tabasi, Samy Hocine

Laser powder bed fusion (L-PBF) is a versatile additive manufacturing process that can print geometrically complex metal parts for a variety of applications. However, poor control of defect formation during processing hampers its widespread industrial adop ...

ELSEVIER2022

Understanding Thermomechanical Treatments Induced by Laser Powder Bed Fusion Process

Hossein Ghasemi Tabasi

Additive Manufacturing (AM) is referred to technologies that produce directly 3D parts in a layer-by-layer fashion. Laser Powder Bed Fusion (L-PBF) is one of the most important AM processes, enabling production of very complex metallic objects from a compu ...

EPFL2021

Influence of Hf on the heat treatment response of additively manufactured Ni-base superalloy CM247LC

Roland Logé, Jamasp Jhabvala, Christian Leinenbach, Hossein Ghasemi Tabasi, Shreyas Sanjay Joglekar

The influence of Hf on the heat treatment response of a Laser Powder Bed Fusion (L-PBF) fabricated Ni-base superalloy was investigated. A Hf-free version of CM247LC, CM247LC NHf, and CM247LC (similar to 1.4 wt% Hf) were subjected to identical thermal treat ...

ELSEVIER SCIENCE INC2021

Mapping Spatial Distribution of Pores in an Additively Manufactured Gold Alloy Using Neutron Microtomography

Roland Logé, Jamasp Jhabvala, Hossein Ghasemi Tabasi, Markus Strobl, Michaël Meyer

A crucial criterion for the quality of the additively manufactured parts is the porosity content for achieving an acceptable final relative density. In addition, for jewelry applications, visible pores are unacceptable at or in the vicinity of the surface. ...

2021

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

Roland Logé, Christian Leinenbach, Jamasp Jhabvala, 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

An effective rule for translating optimal selective laser melting processing parameters from one material to another

Roland Logé, Jamasp Jhabvala, Eric Boillat, Rita Drissi Daoudi, Hossein Ghasemi Tabasi, Toni Ivas

Selective Laser Melting (SLM) or Laser Powder Bed Fusion (L-PBF) is the most studied laser-based additive manufacturing process for metals and alloys. One important issue in SLM is the time-consuming identification of a process window leading to quasi full ...

2020

Healing cracks in selective laser melting by 3D laser shock peening

Roland Logé, Jamasp Jhabvala, Christian Leinenbach, Nikola Kalentics, Navid Sohrabi, Hossein Ghasemi Tabasi, Andreas Burn

Selective Laser Melting (SLM) of Ni-based superalloys such as CM247LC is prone to weld-cracking. This paper investigates how to suppress cracks by repeatedly applying Laser Shock Peening (LSP) during the building phase of SLM. Samples made of CM247LC were ...

ELSEVIER2019