A5034721582- Microstructure and mechanical properties
- Shape Memory Alloy Transformations
- Intermetallics and Advanced Alloy Properties
- Metal and Thin Film Mechanics
- Microstructure and Mechanical Properties of Steels
- High Temperature Alloys and Creep
- High-pressure geophysics and materials
- Metallurgical and Alloy Processes
- Nonlocal and gradient elasticity in micro/nano structures
- High-Velocity Impact and Material Behavior
- MXene and MAX Phase Materials
- High Entropy Alloys Studies
- Magnetic and transport properties of perovskites and related materials
- Magnetic Properties of Alloys
- Material Properties and Failure Mechanisms
- Synthesis and Properties of Aromatic Compounds
- Aluminum Alloys Composites Properties
- Numerical methods in engineering
- Central European Literary Studies
- Polymer composites and self-healing
- Electromagnetic Effects on Materials
- Advanced ceramic materials synthesis
- 2D Materials and Applications
- Transport and Logistics Innovations
- Carbon Nanotubes in Composites
Brno University of Technology
2013-2024
Central European Institute of Technology
2013-2024
Charles University
2022
Czech Academy of Sciences, Nuclear Physics Institute
2022
Czech Academy of Sciences, Institute of Physics
2022
Czech Academy of Sciences, Institute of Physics of Materials
2013-2019
Norwegian University of Science and Technology
2015
Current synthetic elastomers suffer from the well-known trade-off between toughness and stiffness. By a combination of multiscale experiments atomistic simulations, transparent unfilled elastomer with simultaneously enhanced stiffness is demonstrated. The designed comprises homogeneous networks ultrastrong, reversible, sacrificial octuple hydrogen bonding (HB), which evenly distribute stress to each polymer chain during loading, thus enhancing stretchability delaying fracture. Strong HBs...
Four different models (corresponding to loading conditions) of first principles tensile tests are employed determine cohesion and strength several interfaces, namely coherent interfaces two fcc metals (Ni/Ag Ni/Cu) symmetrical tilted Σ5(210) grain boundary in nickel (clean as well sulfur-decorated). The purpose this study is compare the selected critically discuss their advantages limitations. Particular attention paid differences predictions, ability identify weakest link studied system...
We present an ab initio and atomistic study of the stress-strain response elastic stability ordered Fe 3 Al compound with D0 structure a disordered Fe-Al solid solution 18.75 at.% as well nanocomposite consisting equal molar amount both phases under uniaxial loading along [001] direction. The tensile tests were performed complex conditions including effect lateral stress on strength temperature effect. By comparing behavior individual that we find phase represents weakest point studied in...
This work demonstrates a simple but efficient way as to how determine the existence of shear instabilities in ideal bcc crystals under uniaxial loading. The theoretical tensile strengths are derived from calculated values strength and their dependence on superimposed normal stress. presented procedure enables us avoid complicated time-consuming analyses elastic stability crystals. Results first-principles simulations coupled deformations for two most frequent slip systems...
The extraordinary deformation and loading capacity of nine different [∞]carbohelicene springs under uniaxial tension up to their fracture were computed using the density functional theory. simulations comprised either experimentally synthetized hexagonal rings or hypothetical ones that contained irregularities (defects) as, for example, pentagons replacing hexagons. results revealed presence such defects can significantly improve mechanical properties. maximum reversible strain varied from...
Abstract Principles and advantages of a new concept based on the ab initio aided strain gradient elasticity theory are shown in comparison with classical Barenblatt cohesive model. The method is applied to theoretical prediction critical energy release rate crack tip opening displacement at instability nanopanels made germanium molybdenum crystals. necessary length scale parameter l 1 determined for by best fits computed screw dislocation displacements phonon dispersions. Values rates...
There are two sources of quantitative data on grain boundary segregation: careful experimental results and calculated data. These values can be compared in various ways. Here we show a comparison average concentrations silicon, vanadium, tin at the boundaries bcc iron determined three ways: (i) basis calculations segregation energy for individual sites; (ii) experimentally; (iii) using phenomenological prediction selected systems characterized by satisfactory solid solubility segregant bulk....
The study of the effects impurity on grain boundaries is a critical aspect materials science, particularly when it comes to understanding and controlling properties for specific applications. One related key issues segregation preference atoms in boundary region. In this paper, we employed on-the-fly machine learning generate force fields, which were subsequently used calculate energies phosphorus silicon bcc iron containing ∑5(310)[001] boundary. generated fields successfully benchmarked...
Results are given of a fractographic study biaxial in-phase bending/torsion fatigue fractures in specimens made nitrided steel and nickel-based superalloy with protective coatings (diffusion plasma-sprayed thermal barrier coatings). Fracture surfaces were examined by optical scanning electron microscopes while stereophotogrammetry profilometry employed to obtain 3D surface data selected fracture regions. The studied materials exhibited wide range mechanisms depending on the microstructure...
NiTi shape memory alloy has been widely used in many engineering applications (e.g.mechatronic devices, medical tools, seismic sensors etc.).In this work, the Young's moduli of twinned martensite selected crystallographic directions are calculated from first principles and compared with previous data for perfect (untwinned) structure.The obtained results show that twinning mode does not have a significant influence on and, thus, their reduction observed some experiments is probably caused by...
The cohesive strength of Σ 3, 5, and 11 grain boundaries (GBs) in clean hydrogen-segregated fcc nickel was systematically studied as a function the superimposed transverse biaxial stresses using ab initio methods. obtained results for H-free GBs revealed quite different response coherent twinning boundary 3 to applied comparison other GB types. While 5 increased with increasing level tensile stresses, remained constant any levels stresses. In case segregated hydrogen, distinctly reduced all...
We performed a quantum-mechanical molecular-dynamics (MD) study of Fe3Al with and without hydrogen atoms under conditions uniaxial deformation up to the point fracture. Addressing long-lasting problem hydrogen-induced brittleness iron-aluminides ambient conditions, we our density-functional-theory (DFT) MD simulations for T = 300 K (room temperature). Our calculations include series H concentrations ranging from 0.23 4 at.% show clear preference tetrahedral-like interstitial positions within...
The impact of shear deformation in $(1\,0\,1)[1\,0\,\bar{1}]$ system non-modulated (NM) martensite Ni$_2$MnGa ferromagnetic shape memory alloy is investigated by means ab initio atomistic simulations. associated with twinning NM lattice and intermatensitic transformation to modulated structures. stability the increases increasing content Mn. most realistic mechanism for twin reorientation can be approximated simple mechanism, although lowest barriers were calculated pure mechanism. energy...