Computational and Experimental Mechanics of Advanced Materials
September 8, 2008 — September 12, 2008
Coordinator:
- Vadim V. Silberschmidt (Loughborough University, Loughborough, Leicestershire, Great Britain)
Advanced materials (composites, multiphase materials, materials for microelectronics, biomaterials, etc.) play a crucial role in various modern engineering and biomechanical applications where they are often exposed to complex loading and environmental conditions. In many cases, new approaches are needed that explicitly account for microstructural effects on the global performance of advanced materials, components and structures. Such approaches should be calibrated and validated by specific experimental techniques, quantifying both microstructural features and respective mechanisms at various scales.
The aim of the course is to give an overview of various modelling tools and experimental techniques that can be employed to analyse and estimate properties of advanced materials.
The proposed course will have a short introduction into the topic, emphasizing current challenges to mechanics due to advanced materials and their novel applications, i.e., multi-material joints, multi-functional components, continuing miniaturisation, exposure to harsh environments, etc. These challenges should be adequately reflected in modern experimental methods, analytical approaches and computational techniques and provide a researcher with adequate tools to characterise various features of these materials and to model their deformational behaviour, failure processes as well as reliability of components and structures under various conditions.
An overview of classical and current techniques available to characterise material microstructures by light and electron microscopy, X-ray and neutron diffraction will be given. Special emphasis will be on techniques, which allow information to be extracted for various length scales, providing the possibility to gain quantitative microstructural information needed for material modelling and/or experimental validation of model predictions. State-of-the-art methods for acquiring a local crystallographic texture via EBSD and chemistry via EDS and WDS will be presented as well as techniques for characterisation of residual stresses in advanced materials. A presentation of these methods will be accomplished by a discussion of advanced mechanical techniques such as TSA, nanoindentation, testing at the micro-scale and multi-impact testing.
Another part of the course will deal with modern theoretical approaches used for heterogeneous materials and a non-linear material behaviour. One topic will cover the influence of microstructures in composite materials on wave propagation. Another topic will deal with the formulation of a 3-D brick Cosserat Point Element (CPE) for the solution of problems in nonlinear elasticity. The CPE is a user-friendly element that exhibits no locking for nearly incompressible materials and for thin structures, like plates and shells.
A considerable emphasis will be on advanced numerical modelling schemes. One series of lectures will be dedicated to computational problems of nanomechanics and micromechanics of advanced materials. Another series will cover numerically based continuum modelling of thermomechanical and thermophysical behaviours of inhomogeneous materials, e.g. composites, cellular materials and bone tissue.
In addition, several case studies will be analysed in order to demonstrate the strategies used to solve the real-life problems where the microstructure of materials directly affects the response of materials/components/structures to loading and/or environmental conditions. Among the presented examples there will be studies of the reliability of lead-free chip-flip microelectronic packages, damage evolution in ceramic coatings under a laser-induced thermal shock and delamination in adhesive composite joints under conditions of standard and impact fatigue.
The course is addressed to doctoral students, young researchers as well as practicing R&D engineers, dealing with advanced materials, components and structures.