Key project information

Implementation period

Funding

Project Annotation

The project aims to establish an internationally recognized research team studying complex problems of nonlinear dynamic behaviour of modern materials. The project focuses on the theory of nonlinear dynamics and stress wave propagation as well as on experiments with mechanical static, cyclic and dynamic loading in macro- and nano- scales with the influence of surface properties, ambient, corrosive and thermal conditions on degradation and ageing using modern instrumentation and a broad international cooperation.

Goals of the Project

• Establish a stable, internationally-recognized research team
• Create first-rate infrastructure and technical conditions for team’s research
• Develop strategic partnerships

What problem does the Project solve?

The project focuses on the problem of nonlinear dynamic behaviour of modern and advanced materials, especially on the theroy of nonlinear dynamics and on experimental research of mechanical behaviour under static and dynamic cyclic loading in macro- and nano- scales with the influence of surface properties and the ambience on the behaviour of materials, especially their surface.

Theoretical research

The theoretical research within the project will tackle the following problems:

• Development of directional and kinematic hardening models, plasticity models with finite strains, models of ductile damage and ductile fracture and plasticity models for metals with porous structure
• Stress wave propagation in laminated, gradated and generally heterogeneous and anisotropic materials and stress wave propagation in thermo-elastic environment
• Application of the proposed models of plasticity in finite strains undergoing dynamic loading
• Development of methods based on molecular dynamic simulation for wave propagation problems and deformation processes at atomic level, ductile-brittle transition and dynamic crack propagation

Experimental research

Experimental parts of the project are solved in correlation with theoretical parts, how improve duality current possibilities on the base enlargement of possibilities in evaluation of behaviour of materials during uniaxial also multiaxial static, quasistatic and fatigue loading in elastic, elastic plastic and marked plastic deformation for theoretical models of plasticity. Further there are solved problems of evaluation step by step created changes during cyclic loading by very sensitive methods of evaluation local properties and behaviour namely in surface layers also in small localities, profiling of changes across selected cross sections of different loaded volumes, influence of surface layers, degradation and ageing process from initiation to the critical estate on mechanical behaviour of metals, polymeric materials also composite materials.

Research activities

• Development of existing models of directional and kinematic hardening metals plasticity, polynominal models involvement; cross-effect impact modelling.
• Porous materials plasticity.
• Development of correct plasticity models for finite strains, incl. numerical implementation.
• Development of methodology for evaluation of surface layers by technology created or created by degradation process and for evaluation of local properties in inhomogeneity of material system.
• Study step by step changing in surface of material and selected cross sections of material after step by step static and fatigue loading with using very sensitive analytic methods namely nanoindentation.
• Study of influence of temperature conditions, corrosive and climatic conditions on behaviour of materials during static and fatigue loading with monitoring step by step changes from surface and selected cross sections by sensitive analytic methods namely nanoindentation.
• Study of ageing of polymeric and composite materials – experimental simulation of ageing by temperature loading, action of humidity and sun radiation and study of changing in progress by sensitive analytic methods namely nanoindentation and x-ray fluorescent analysis for capture initiation of ageing, in sequential expansion and evaluation of critical estate of selected materials and material system.
• Stress waves propagation in flexible bodies focus on waves propagation in laminated, gradated and in general heterogenous and anisotropic materials; analytical and numerical methods development and related experiments; development of acoustic lens and methods for controll waves propagation by composition of gradated samples and their geometry.
• Waves propagation in thermo-elastic environment, associated thermomechanic task.
• Material behavior study during dynamical loading (dynamic plasticity); experimental research of material behavior during dynamical loading with fenomenological dynamic models (Hopkinson rods) parameters identification.
• Application of proposed models of plasticity for large deformation/finite strains during dynamical loading (Taylor tests).
• Development of methods molecular dynamics for waves propagation and methods for description of damage processes at athomic level; ductile-brittle transition and dynamic expansion of cracks.

Contact:

Project Manager: Dr. Dušan Gabriel