Person
Efthymios Polatidis
This person is no longer with EPFL
Related publications (13)
Bragg edge tomography characterization of additively manufactured 316L steel
Roland Logé, Christian Leinenbach, Efthymios Polatidis, Markus Strobl, Nikola Kalentics
In this work we perform a neutron Bragg edge tomography of stainless steel 316L additive manufacturing samples, one as built via standard laser powder bed fusion, and one using the novel three-dimensional (3D) laser shock peening technique. First, we consi ...
AMER PHYSICAL SOC2022Tailored deformation behavior of 304L stainless steel through control of the crystallographic texture with laser-powder bed fusion
Roland Logé, Christian Leinenbach, Efthymios Polatidis, Markus Strobl
Laser-powder bed fusion (L-PBF) has gained significant research interest, not only for its profound advantage of producing near-net shape complex geometries of metallic parts, but also for the possibility of producing tailored microstructures. Here we expl ...
ELSEVIER SCI LTD2022The effect of stress triaxiality on the phase transformation in transformation induced plasticity steels: Experimental investigation and modelling the transformation kinetics
Helena Van Swygenhoven, Efthymios Polatidis, Nicola Casati
In situ multiaxial loading during neutron diffraction tests were undertaken on a low-alloyed Quenched and Partitioning (Q&P) Transformation Induced Plasticity (TRIP) Bainitic Ferrite (TBF) steel with dispersed austenite particles. The effect of stress tria ...
2021Measurement and prediction of the transformation strain that controls ductility and toughness in advanced steels
William Curtin, Helena Van Swygenhoven, Efthymios Polatidis, Francesco Maresca
New-generation multi-phase martensitic steels derive their high strength from the body-centered cubic (BCC) phase and high toughness from transformation of the metastable face-centered cubic (FCC) austenite that transforms into martensite upon loading. In ...
PERGAMON-ELSEVIER SCIENCE LTD2020Neutron Diffraction and Diffraction Contrast Imaging for Mapping the TRIP Effect under Load Path Change
Helena Van Swygenhoven, Efthymios Polatidis, Markus Strobl
The transformation induced plasticity (TRIP) effect is investigated during a load path change using a cruciform sample. The transformation properties are followed by in-situ neutron diffraction derived from the central area of the cruciform sample. Additio ...
MDPI2020Deformation mechanisms in a superelastic NiTi alloy: An in-situ high resolution digital image correlation study
Helena Van Swygenhoven, Efthymios Polatidis
An in-situ high resolution digital image correlation investigation during uniaxial tensile deformation reveals the recoverable and the non-recoverable strain mechanisms in a Ni51Ti49 alloy with a mean grain size of 35 mu m. Recoverable strain is due to the ...
2020Characterization, mechanical properties and dimensional accuracy of a Zr-based bulk metallic glass manufactured via laser powder-bed fusion
Roland Logé, Steven Van Petegem, Jamasp Jhabvala, Antonia Neels, Efthymios Polatidis, Annapaola Parrilli, Güven Kurtuldu, Navid Sohrabi
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 ...
2020The interplay between deformation mechanisms in austenitic 304 steel during uniaxial and equibiaxial loading
Helena Van Swygenhoven, Efthymios Polatidis, Wei-Neng Hsu
The preferred deformation mechanisms with respect to the load path are studied in a medium stacking fault energy 304 austenitic stainless steel that exhibits both transformation induced plasticity and twinning induced plasticity. In situ neutron diffractio ...
2019Following Microstructures during Deformation: In situ X-ray/Neutron Diffraction and HRDIC
Helena Van Swygenhoven, Efthymios Polatidis
The mechanical behavior of three engineering materials is studied employing in situ deformation methods. The study covers metastable austenitic steels with different stacking fault energies during multiaxial loading, a Ti-6Al-4V alloy processed by electron ...
IOP PUBLISHING LTD2019A High Resolution Digital Image Correlation Study under Multiaxial Loading
Helena Van Swygenhoven, Efthymios Polatidis, Wei-Neng Hsu
In this study, a miniaturized cruciform-shaped sample geometry which allows reaching high plastic strain under equibiaxial loading with reduced thickness at the test section is presented. The thinning method results in excellent surface quality that can be ...
SPRINGER2019