Publications by Jamasp Jhabvala

Avoiding cracks in multi-material printing by combining laser powder bed fusion with metallic foils: Application to Ti6Al4V-AlSi12 structures

Eric Boillat, Jamasp Jhabvala, Roland Logé

Laser powder bed fusion (LPBF) as an additive manufacturing (AM) technology has emerged as a powerful platform for producing multi-material metallic structures. The main drawbacks of using metallic powders for multi-material printing are related to technic ...

2025

Formation mechanism and microstructural characteristics of a body-centered cubic phase in 3D printed 316L–CuCrZr multi-material structures, combining laser powder bed fusion with foils

Cyril Cayron, Jamasp Jhabvala, Roland Logé

Additive manufacturing of 316L/CuCrZr multi-material metallic structures has recently attracted significant attention, due to the ideal combination of structural and thermal/electrical properties. In this work, a unique multi-phase microstructure was produ ...

2025

Toward Architected Microstructures Using Advanced Laser Beam Shaping in Laser Powder Bed Fusion of Ti-6al-4v

Mathijs Pieter van der Meer, Eric Boillat, Cyril Cayron, Jamasp Jhabvala, Roland Logé, Junfeng Xiao

Laser Powder Bed Fusion (LPBF) stations mostly use lasers with a Gaussian beam intensity distribution, as it has advantages like small divergence and high ability to be focused. This distribution creates significant thermal gradients leading to high coolin ...

WILEY-V C H VERLAG GMBH2025

Fast and accurate laser powder bed fusion metamodels predicting melt pool dimensions, effective laser absorptivity and lack of fusion defects

Eric Boillat, Jamasp Jhabvala, Roland Logé, Milad Hamidi Nasab

The significant computational expenses associated with simulating the Laser Powder Bed Fusion (LPBF) process often restrict the insights gained from modeling endeavors to specific combinations of process parameters, hindering broader conclusions. In this s ...

2025

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

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

Acoustic emission signature of martensitic transformation in laser powder bed fusion of Ti6Al4V-Fe, supported by operando X-ray diffraction

Mathijs Pieter van der Meer, Jamasp Jhabvala, Roland Logé, Milad Hamidi Nasab

This study focuses on investigating Acoustic Emission (AE) monitoring in the Laser Powder Bed Fusion (LPBF) process, using premixed Ti6Al4V-(x wt%) Fe, where x = 0, 3, and 6. By employing a structure-borne AE sensor, we analyze AE data statistically, uncov ...

2024

Laser powder-bed fusion of a high entropy alloy with outstanding intrinsic mechanical properties

Cyril Cayron, Jamasp Jhabvala, Václav Pejchal, Roland Logé, Navid Sohrabi

In the past few years, laser powder-bed fusion (LPBF) of high entropy alloys (HEAs) has gained significant interest. We investigated a HEA (PdPtRhIrCuNi) elaborated by LPBF, and studied its microstructure and mechanical properties. This alloy has potential ...

ELSEVIER SCIENCE SA2023

Acoustic emission for the prediction of processing regimes in Laser Powder Bed Fusion, and the generation of processing maps

Jamasp Jhabvala, Rita Drissi Daoudi, Roland Logé

The Laser Power Bed Fusion (LPBF) process is of high interest to many industries, such as motors and vehicles, robotics, biomedical applications, aerospace, and others. LPBF workpieces can indeed achieve near full density and high resistance. However, a la ...

ELSEVIER2023

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

Eric Boillat, Cyril Cayron, Jamasp Jhabvala, Roland Logé, 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

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

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

Additive Manufacturing of Bulk Metallic Glasses-Process, Challenges and Properties: A Review

Jamasp Jhabvala, Roland Logé, Navid Sohrabi

Bulk Metallic Glasses (BMG) are metallic alloys that have the ability to solidify in an amorphous state. BMGs show enhanced properties, for instance, high hardness, strength, and excellent corrosion and wear resistance. BMGs produced by conventional method ...

MDPI2021

Additive manufacturing of a precious bulk metallic glass

Jamasp Jhabvala, Güven Kurtuldu, Antonia Neels, Roland Logé, Navid Sohrabi, Annapaola Parrilli

For the first time, a high-density amorphous and crack-free bulk metallic glass (BMG) based on a precious metal (PdCuNiP) was produced via additive manufacturing (AM). Laser powder-bed fusion (LPBF) was used for the fabrication of the samples, and led to a ...

2021

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

Jamasp Jhabvala, Christian Leinenbach, Roland Logé, 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

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

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

Fatigue Performance of an Additively Manufactured Zr-Based Bulk Metallic Glass and the Effect of Post-Processing

Jamasp Jhabvala, Roland Logé, Navid Sohrabi, Milad Hamidi Nasab, Baptiste Thomas Jean Rouxel, Annapaola Parrilli

Fatigue is the most common cause of failure of mechanical parts in engineering applications. In the current work, we investigate the fatigue life of a bulk metallic (BMG) glass fabricated via additive manufacturing. Specimens fabricated via laser powder-be ...

MDPI2021

Critical crystallization properties of an industrial-grade Zr-based metallic glass used in additive manufacturing

Jamasp Jhabvala, Roland Logé, Navid Sohrabi

The major challenge to overcome when processing metallic glasses (MGs) is to avoid crystallization. Therefore, time-temperature-transformation (TTT) diagrams are used, but they are often derived from experiments in which heating or cooling rates are limite ...

2021

Tensile and Impact Toughness Properties of a Zr-Based Bulk Metallic Glass Fabricated via Laser Powder-Bed Fusion

Jamasp Jhabvala, Antonia Neels, Roland Logé, Navid Sohrabi, Annapaola Parrilli

In the past few years, laser powder-bed fusion (LPBF) of bulk metallic glasses (BMGs) has gained significant interest because of the high heating and cooling rates inherent to the process, providing the means to bypass the crystallization threshold. In thi ...

MDPI2021

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

Laser coating of a Zr-based metallic glass on an aluminum substrate

Stefano Mischler, Jamasp Jhabvala, Alejandro Roda Buch, Roland Logé, Navid Sohrabi

Cladding of a Zr-based metallic glass (MG) on an aluminum substrate was conducted using a layer-wise laser additive manufacturing (AM) method, leading to relative densities higher than 99%. The thickness of the cladding was about 300 μm. The effect of lase ...

2020

Characterization, mechanical properties and dimensional accuracy of a Zr-based bulk metallic glass manufactured via laser powder-bed fusion

Jamasp Jhabvala, Güven Kurtuldu, Steven Van Petegem, Antonia Neels, Roland Logé, Efthymios Polatidis, Navid Sohrabi, Annapaola Parrilli

Bulk metallic glasses (BMGs) are high-strength, highly elastic materials due to their disordered atomic structure. Because BMGs require sufficiently high cooling rates to bypass crystallization, laser-based additive manufacturing (AM) methods have recently ...

2020