Projects
AMS 01 01 Light elements in iron and steel: application to Boron
Boron is a common additive element in steel production and, although the usual quantity rarely exceeds a few parts per million (ppm), it has a large impact on the mechanical properties of the material.... Continue reading "Light elements in iron and steel: application to Boron"AMS 01 02 Atomistic modelling of the Fe-C system
AMS 01 03 Light elements in iron and steel: Interfaces
The central goal of the project was to contribute to the understanding of hydrogen embrittlement in steels on the atomistic level by density-functional theory calculations. The addressed aspects include... Continue reading "Light elements in iron and steel: Interfaces"AMS 01 05 Development and application of tight binding methods for magnetism and light elements in steel
For a systematic design of steels with specific properties a detailed atomistic understanding of the bonding mechanisms and energetics is necessary. The basis of this understanding is the tight binding... Continue reading "Development and application of tight binding methods for magnetism and light elements in steel"AMS 03 01 Atomistic modelling of the kinetics of solid-solid phase transformations
In solidification theory the properties of solid-liquid interfaces such as the interface energy, interface mobility, anisotropy etc., are of great interest since they determine to a large extend the nucleation... Continue reading "Atomistic modelling of the kinetics of solid-solid phase transformations"AMS 03 03 Atomistic simulations of structural rearrangements at solid-solid interfaces
A common problem in high-performance materials such as Ni-base superalloys is the formation of topologically close-packed (TCP) phases, which deprive the bulk matrix of the alloying refractory metals and... Continue reading "Atomistic simulations of structural rearrangements at solid-solid interfaces"AMS 09 01 Properties and chemistry of the Fe and Zn interfaces
For a systematic understanding of corrosion protection it is necessary to obtain a detailed atomistic understanding of the bonding mechanisms and energetics at interfaces and surfaces. The basis of this... Continue reading "Properties and chemistry of the Fe and Zn interfaces"AMS 12 01 Development of analytic bond-order potentials for the simulation of complex intermetallic phases
AMS 12 02 Atomistic simulation of the kinetics of tcp formation
AMS 13 01 Charge transfer in the atomistic simulation of carbide and nitride nanocomposite coatings
AMS 13 02 Development and application of bond-order potentials for SiC-TiC nanocomposite coatings
CMD 09 01 Multiscale simulations of H embrittlement in metals: Application to the HELP mechanism
The prospect of a hydrogen-based economy critically depends on the availability of structural materials that can withstand extended exposure to hydrogen. Most metals, and in particular high strength steels,... Continue reading "Multiscale simulations of H embrittlement in metals: Application to the HELP mechanism"CMD 09 02 Chemical trends for hydrogen-vacancy complexes and resulting self-diffusion parameters
The interaction of H with vacancies in metals can be the reason for several hydrogen-related processes. Since vacancies serve as trapping centers for dissolved H, they locally yield a critical H concentration... Continue reading "Chemical trends for hydrogen-vacancy complexes and resulting self-diffusion parameters"CMD 10 01 Polymer Structure at Interfaces and Ion Diffusion Mechanisms
Polymer coatings are used for corrosion protection in many applications. Diffusion of ions (galvanic coupling) as well as small molecules (O2, H2O) along the metal/polymer interface and close to the interface... Continue reading "Polymer Structure at Interfaces and Ion Diffusion Mechanisms"CMD 10 02 Polymer/metal interface structure and adhesion
Cohesively bonded polymer-solid interfaces are essentially required for all kinds of applications such as protective coatings and metal-polymer compound systems. A feature that characterizes these interfaces... Continue reading "Polymer/metal interface structure and adhesion"DFG VA205/3 2 Static and dynamic critical phenomena
Although critical phenomena have widely been investigated in the literature, almost all these studies consider the case of energy conserving systems. In particular, –to the best of our knowledge- no... Continue reading "Static and dynamic critical phenomena"DFG WENDELIB 11.1 Spatially resolved modelling and characterization of (de-)intercalation in Li-Ion battery materials: DFT calculations (SP1)
Lithium ion battery materials undergo significant volume change during charging and discharging, which, dependent on the material, is connected to a change of the crystallographic structure. This causes... Continue reading "Spatially resolved modelling and characterization of (de-)intercalation in Li-Ion battery materials: DFT calculations (SP1)"EXT 04 01 Flow heterogeneity and non-linear response in amorphous solids
When imposed to an external load, crystalline materials usually yield along well defined spatial directions which are closely determined by the structure of the crystal and the relative orientation of... Continue reading "Flow heterogeneity and non-linear response in amorphous solids"EXT 08 01 Heterogeneous nucleation and microstructure formation
Guillaume BoussinotRobert SpatschekMax-Planck Institute for Iron Research, Düsseldorf Heterogeneous nucleation and the growth of microstructures are often accompanied by elastic deformations... Continue reading "Heterogeneous nucleation and microstructure formation"EXT 08 02 Modelling of pine-tree nanowires
Rainer SchulzRobert Spatschek Max-Planck Institute for Iron Research, Düsseldorf Nanowires are thin wires (e.g. metal) which are severely restricted in 2 dimensions of space and show a one-dimensional... Continue reading "Modelling of pine-tree nanowires"IEHK 05 01 Microstructure based evaluation of real structures in cold formable steels
Multi-phase steel has unique mechanical properties because of its interplay between high strength and good uniform elongation properties. This is due to the fact that the microstructure is made up of constituents... Continue reading "Microstructure based evaluation of real structures in cold formable steels"IEHK 05 03 Microstructure based evaluation of real structures in cold formable steels II
This project shall continue the work performed in IEHK-05-01 and consists of four tasks; micromechanical damage modelling of multiphase steels, study effects of microstructure morphology on failure behaviour... Continue reading "Microstructure based evaluation of real structures in cold formable steels II"IEHK 05 04 Microstructure based evaluation of real structures in cold formable steels III
The project shall finalises the work performed on the same topic from 2009 to 2013. During the first period of the project, initially an adequate heat treatment was developed by experimental and numerical... Continue reading "Microstructure based evaluation of real structures in cold formable steels III"IEHK 06 01 Effect of microstructure on the growth of short cracks
The main purpose of this project is to develop a multi-scale model to quantitatively describe the effect of microstructure constituents on micro crack fatigue growth. Due to the known difficulty when simulating... Continue reading "Effect of microstructure on the growth of short cracks"IEHK 06 02 Microstructural influences on growth of short cracks in steel under cyclic loading II
The metallurgical concepts for the improvement of cyclic properties of modern steels are based on the reducing of impurities in a microstructure. A few remaining particles can be responsible for unexpected... Continue reading "Microstructural influences on growth of short cracks in steel under cyclic loading II"IEHK 06 03 Microstructural influences on growth of short cracks in steel under cyclic loading III
The project shall finalize the work performed on the same topic. One of the main purposes of this project is to develop a microstructural model for the simulation of fatigue micro crack growth. In the... Continue reading "Microstructural influences on growth of short cracks in steel under cyclic loading III"LWW 03 01 Functional and structural fatigue of shape memory alloys
LWW 03 02 Phase stabilities and martensitic transformations in Ti-Ta alloys
The proposed work is required as a start-up project for a new DFG research group on high temperature shape memory alloys. The aim is to provide preliminary results that are urgently required for the initial... Continue reading "Phase stabilities and martensitic transformations in Ti-Ta alloys"LWW 05 01 Experimental and theoretical investigation of micro-shear processes in fcc metals
The task of this project is to combine theoretical and experimental methods for the investigation of micro-plasticity during shear deformation in fcc metals..Continue reading "Experimental and theoretical investigation of micro-shear processes in fcc metals"LWW 14 01 Creep, microstructure evolution and crack growth in precipitation hardened microstructures
The project aims on investigations of the mechanical anisotropy and microstructural evolution during high temperature / low stress creep of a single crystalline Ni-based superalloy. Tests are performed... Continue reading "Creep, microstructure evolution and crack growth in precipitation hardened microstructures"LWW 14 02 Deformation and fracture mechanisms in TiAl alloys
In the present project, we investigate deformation and fracture mechanisms of g-TiAl alloys. In particular, modern 3rd generation high-Nb containing TNB alloys are under investigation, one with a fine-grained... Continue reading "Deformation and fracture mechanisms in TiAl alloys"MMM 01 01 Coupled atomistic-FEM analysis of light elements at dislocation cores
The influence of light elements on the mobility of dislocations and thus on the deformation behaviour of a material strongly depends on the details of the interatomic interactions, which makes an atomistic... Continue reading "Coupled atomistic-FEM analysis of light elements at dislocation cores"MMM 02 01 Multiscale modelling of fracture at grain boundaries
Fracture is a multi-scale phenomenon in which the process starts at atomistic level by breaking of bonds in front of the crack tip. Subsequently this damage progression leads to macroscopic failure modes... Continue reading "Multiscale modelling of fracture at grain boundaries"MMM 02 02 Grain boundaries in polycrystals: Bridging the scales
MMM 02 04 Grain boundary mechanics: universal description and coarse graining
To gain a better understanding of deformation of polycrystals, we investigate the mechanisms of grain boundary and bulk deformation under a combination of shear and tensile strain by means of ab-initio... Continue reading "Grain boundary mechanics: universal description and coarse graining"MMM 02 05 Influence of coherency strain on the stability of carbide precipitates in bcc metals
Within the framework of ab-initio calculations, we investigate the eff ect of lattice parameter mismatch on the interface between the matrix of pure molybdenum, Mo and a carbide, MoCx and predict the... Continue reading "Influence of coherency strain on the stability of carbide precipitates in bcc metals"MMM 05 01 Plasticity in Polycrystals: Dislocations and Grain Boundaries
In ultra-fine grained and nanocrystalline materials the grain boundary region has a rather large volume fraction and therefore the dislocation glide becomes increasingly difficult. Hence, to describe... Continue reading "Plasticity in Polycrystals: Dislocations and Grain Boundaries"MMM 05 02 MD study of plastic deformation by dislocations and phase transformations
Shape memory alloys (SMA) like Ni-Ti show a characteristic phase transformation between a martensite and an austenite phase depending on temperature and mechanical stress. The change in shape during transformation... Continue reading "MD study of plastic deformation by dislocations and phase transformations"MMM 05 03 Plastic deformation by phase transformation: constitutive descriptions of TRIP steels
TRIP (TRansformation Induced Plasticity) steels count among the group of high-strength steels. They exhibit high strength and ductility at the same time. These characteristics can be traced back to the... Continue reading "Plastic deformation by phase transformation: constitutive descriptions of TRIP steels"MMM 06 01 Brittle-to-ductile transition in tungsten single and polycrystals: Microstructure and failure mechanisms
MMM 06 02 Scale bridging modeling of hydrogen enhanced crack propagation in steels
Hydrogen embrittlement (HE) affects the loading capacity and toughness of almost all metals, in particular of high-strength steels. To understand the huge amounts of experimental findings, many mechanisms... Continue reading "Scale bridging modeling of hydrogen enhanced crack propagation in steels"MMM 06 03 Multiscale modelling of adhesion of polymer coatings on rough surfaces
Polymer coated metals sheets are extensively used in various applications such as food-packaging and automotive industry. The metal – polymer hybrids are deep-drawn during production to obtain the final... Continue reading "Multiscale modelling of adhesion of polymer coatings on rough surfaces"MMM 08 01 Solubility of carbon close to defects in bcc iron I
The aim of the present project is to investigate the solubility and segregation behaviour of carbon in the strain field of defects in bcc Fe, such as grain boundaries and dislocations. In order to be... Continue reading "Solubility of carbon close to defects in bcc iron I"MMM 15 01 Micromechanical modelling of fatigue lifetimes in bearing steels
MMM 15 02 Studying Fatigue Crack Initiation with a new Multiscale Model
Discrete dislocation models are capable to describe metal blocks of 2mm side length. However, interactions of dislocations with the evolving fatigue crack are crudely approximated. Molecular dynamics models... Continue reading "Studying Fatigue Crack Initiation with a new Multiscale Model"STKS 02 01 Void drag model for Grain Growth
Multi-phase field (MPF) and molecular dynamics (MD) simulations have been applied to study nanograin growth mechanisms. At mesoscale level, prominent properties of nanostructured materials, e.g. the grain... Continue reading "Void drag model for Grain Growth"STKS 03 01 Plastic effects on the kinetics of phase transformations
STKS 03 02 Gibbs free energy with elasticity
STKS 04 01 Multiscale simulation of metal-polymer hybrid materials
STKS 04 02 Phase behavior of droplets and solid particles in a fluid environment
Understanding phase behavior of droplets and solid particles in a fluid environment is of great interest for a large number of industrial applications ranging from cosmetic and food (e.g., stability and... Continue reading "Phase behavior of droplets and solid particles in a fluid environment"STKS 04 03 Confinement effects on phase behaviour of amorphous solids
A full understanding of the slowing down of transport upon approaching the glass transition is one of the grand challenges of condensed matter theory. A recent focus has been to introduce competing mechanisms... Continue reading "Confinement effects on phase behaviour of amorphous solids"STKS 05 01 Phase field modelling of large deformations
During simulation of phase transformations large lattice parameter changes (i.e. eigenstrains) might occur. The standard linear elasticity which is typically used in phase field simulations proved to be... Continue reading "Phase field modelling of large deformations"STKS 08 02 Secondary-phase particle drag and pinning
Secondary-phase particles are frequently observed in different alloys: light elements, e.g. carbon, boron, nitrogen and oxygen within multicomponent alloys may convert to carbides, borides, nitrides and... Continue reading "Secondary-phase particle drag and pinning"STKS 09 01 Phase-field simulation of diffusion couples
Linking thermodynamic and atomic mobility databases with two-dimensional phase-field simulation, the evolution of interdiffusion microstructures in a series of Ni–Al diffusion couples associated with... Continue reading "Phase-field simulation of diffusion couples"STKS 09 02 Thermodynamics and interdiffusion at interfaces with a potential jump
STKS 09 03 Phase-field simulation of diffusion couples with an augmented multi-phase-field approach
Diffusion couple experiments are effective tools in investigation of alloy thermodynamics and kinetics, but their advantages can be counter balanced by the overlap of different mechanisms. Thus, computer... Continue reading "Phase-field simulation of diffusion couples with an augmented multi-phase-field approach"STKS 16 01 Deformation of the strand shell during peritectic transfomation
As The high susceptibility of peritectic steel grades to hot tearing is a well known problem in metallurgy. It easily happens along the dendrites and grain boundaries on mush zone. If hot tears form between... Continue reading "Deformation of the strand shell during peritectic transfomation"STKS 16 02 3D phase field-lattice Boltzmann modeling of microstructure evolution in binary alloys
The aim of this project is the development of a phase-field based lattice Boltzmann method to investigate the solidification of binary alloys taking into account the effects of diffusion, convection and... Continue reading "3D phase field-lattice Boltzmann modeling of microstructure evolution in binary alloys"STKS 16 03 Spacing selection in columnar peritectic solidification
Solidification of peritectic steel grades in continuous casting is subject to inherent problems due to the peritectic transformation of ferrite to austenite close to the tip of the solidification zone,... Continue reading "Spacing selection in columnar peritectic solidification"STKS 17 01 Solid-State and Viscous Sintering
The project aims on reaching a qualitative understanding about the principal mechanisms of sintering, their relative importance and the feasibility of numerical treatments..Continue reading "Solid-State and Viscous Sintering"STKS 18 02 Kinetics of batteries and related systems
Despite the exciting developments in the field of lithium ion batteries as energy storage devices, there are severe issues restricting their capacity and cycleability, arising e.g. from volume expansion... Continue reading "Kinetics of batteries and related systems"
