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Research Projects

Spinodal decomposition for high-entropy soft magnetic alloys design 
In this project, we work on a generic solution to design advanced high-entropy alloys (HEAs) with enhanced magnetic properties. By overturning the concept of stabilizing solid solutions in HEAs, we propose to render the massive solid solutions metastable and trigger spinodal decomposition. The motivation for starting from the HEA for this approach is to provide the chemical degrees of freedom required to tailor spinodal behaviour using multiple components.
Combinatorial development of Invar alloys via rapid alloy prototyping 
In this project, we work on the use of a combinatorial experimental approach to design advanced multicomponent multi-functional alloys with rapid alloy prototyping. We use rapid alloy prototyping to investigate five multicomponent Invar alloys with 5 at.% addition of Al, Cr, Cu, Mn and Si to a super Invar alloy (Fe63Ni32Co5; at.%), respectively. All the new alloys show a typical Invar effect with low TEC around room temperature.
Ultrastrong and Ductile Soft Magnetic High-Entropy Alloys via Coherent Ordered Nanoprecipitates 
In this project, we aim to realize an optimal balance among the strength, ductility and soft magnetic properties in soft-magnetic high-entropy alloys. To this end, we introduce a high-volume fraction of coherent and ordered nanoprecipitates into the high-entropy alloy matrix. The good combination of strength and ductility derives from massive solid solution, nanoprecipitation and dynamic microband strengthening, yielding mechanical features beyond those reported before for soft magnetic materials. The full coherency of the ordered nanoprecipitates and the matrix contributes significantly to the strength with only a slight increase in coercivity. more
Dual-nanoprecipitation enables ultrastrong lightweight compositionally complex nanosteels
We introduce here a new approach in which we strengthen a low-density solid solution matrix simultaneously by a dual-nanoprecipitation system containing both kappa-carbides and B2 particles. Since the conventional thermodynamic working point is not accessible to realize this dual-precipitation strategy, we designed a low-density (6.6 g/cm3) steel-type alloy, which uses merits of the recently introduced multi–principal element approach referred to as compositionally complex alloys (CCAs) or high-entropy alloys (HEAs).

Interface Segregation Engineering in Additive Manufacturing of a High Entropy Alloy
In this project we study how Segregation Engineering can serve in the design of more robust and crack-free microstructures in Additive Manufacturing. More specific, we were able to reduce hot tearing in additive manufacturing of an Al x CoCrFeNi high-entropy alloy by grain boundary segregation engineering. more
Enhancing mechanical properties of NiCoCr-based medium entropy alloys by tuning multiscale heterogeneous structures
In this project, we aim to design novel NiCoCr-based medium entropy alloys (MEAs) and further enhance their mechanical properties by tuning the multiscale heterogeneous composite structures. This is being achieved by alloying of varying elements in the NiCoCr matrix and appropriate thermal-mechanical processing. more
Cryogenic deformation behavior of an interstitial TRIP high-entropy alloy
This project studies the mechanical properties and microstructural evolution of a transformation-induced plasticity (TRIP)-assisted interstitial high-entropy alloy (iHEA) with a nominal composition of Fe49.5Mn30Co10Cr10C0.5 (at. %) at cryogenic temperature (77 K). We aim to understand the hardening behavior of the iHEA at 77 K, and hence guide the future design of advanced HEA for cryogenic applications. more
Transformation-assisted interstitial quinary high-entropy alloys
In this project, we aim at significantly enhancing the strength-ductility combination of quinary high-entropy alloys (HEAs) with five principal elements by simultaneously introducing interstitial C/N and the transformation induced plasticity (TRIP) effect. Thus, a new class of alloys, namely, interstitially alloyed TRIP-assisted quinary (five-component) HEAs is being developed. more
Recrystallization behavior and mechanical properties of interstitial equiatomic CoCrFeMnNi High-entropy alloys
In this project, we aim to understand the interstitial carbon effect on the recrystallization behavior of the equiatomic CoCrFeMnNi HEA and hence to tune the corresponding mechanical properties. more
Interstitial CoCrNi medium-entropy alloys
In this project, we aim to enhance the mechanical properties of an equiatomic CoCrNi medium-entropy alloy (MEA) by interstitial alloying. Carbon and nitrogen with varying contents have been added into the face-centred cubic structured CoCrNi MEA. more
Atomic scale understanding of the TRIP-assisted dual-phase high-entropy alloys
In this project, we aim to achieve an atomic scale understanding about the structure and phase transformation process in the dual-phase high-entropy alloys (HEAs) with transformation induced plasticity (TRIP) effect. Aberration-corrected scanning transmission electron microscopy (TEM) techniques are being applied ... more
Design of high-temperature refractory high-entropy alloys
In this project, a strategy of combining intermetallic phases and massive solid solutions is employed to design novel Refractory high-entropy alloys (RHEAs). more
Cyclic plasticity and constitutive modeling of transformation assisted interstitial high-entropy alloys
In this project, we perform macro-/microscopic experiments and constitutive modelling to investigate the effects of stress amplitude and mean stress on the ratchetting strain and the overall cyclic behavior of interstitial high-entropy alloys (iHEAs)... more
Design of high and medium entropy alloys with invar effect
In this project, we probe the invar effect in the high and medium entropy alloys over the huge unexplored compositional space. Combining experimental investigation (PPMS, EBSD, ECCI, APT and TEM) and theoretical calculation (DFT and Calphad)... more
Segregations and complexions in high-entropy alloys
In this project, we investigate the segregation behavior and complexions in the CoCrFeMnNi high-entropy alloys (HEAs). The structure and chemistry in the HEAs at varying conditions are being revealed systematically by combining multiple advanced techniques such as electron backscatter diffraction (EBSD) and atom probe tomography (APT). more
Hydrogen embrittlement behavior of high-entropy alloys
In this project, the hydrogen embrittlement mechanisms in several types of high-entropy alloys (HEAs) have been investigated through combined techniques, e.g., low strain rate tensile testing under in-situ hydrogen charging, thermal desorption spectroscopy (TDS),... more
Electrochemical and corrosion behavior of high-entropy alloys
In this project, the electrochemical and corrosion behavior of high entropy alloys (HEAs) have been investigated by combining a micro-electrochemical scanning flow cell (SFC) and an inductively coupled plasma mass spectroscopy (ICP-MS) element analysis. more
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