Course description

The modern engineering is more than ever characterised by the use of all classes of materials and by the possibility of design new materials by adopting new technologies. A clear understanding in the mechanical behaviour of materials is necessary to optimize the material selection, to study the interaction between material and shape and to critically apply design rules in order to avoid unexpected failure of components.

The specifics of the mechanical behaviour of different material classes (metals, ceramics, polymers, elastomers and composites) will be treated in the course. Each material will be studied considering its own peculiarities in terms of specific constitutive laws, strength and specific life assessment methods under complex stress states.

On the other hand, in order to close the gap between theoretical knowledge and practical application the mechanical behaviour of materials will be numerically modelled by adopting the finite element method approach.

Moreover, many problems in engineering and science involve some level of coupling between different physical fields. A multiphysics numerical approach will be adopted in different case studies, such as: fluid-structure interaction and thermo-mechanical coupling.

Course contents

Optimization of materials selection: overview of available materials for the production of components and machinery parts, method of optimal materials selection (Ashby charts).

Polymers: classification, visco-elastic behaviour, hyperelasticity, strength/crazing, elements on the fatigue resistance, numerical identification of the parameters of the material’s models.

Composite materials: reminder of elasticity of anisotropic materials, mechanical characterization, elastic, static and fatigue strength, damage models.

Metals: life cycle assessment methods of components and products under a complex stress states, high and low cycle fatigue (HCF, LCF), elasto-plastic behaviour under cyclic loading, fracture mechanics, crack propagation due to fatigue.

Advanced materials for the design of mechanical components: mechanical characterization, static and fatigue properties of sintered, light alloys, ceramic materials, smart materials and shape memory alloys.

Modelling and Simulation of mechanical behaviour of materials: specific methods of numerical modelling for long fibre composites, laminates and sandwich panels; numerical modelling of metals: elastic and elasto-plastic behaviour in finite element analysis, finite element in fracture mechanics.

Multiphysics approach: interaction between general non-linear structures and general fluid flow, coupled thermo-mechanical problems where the temperature distribution affects the structural deformation.

Experimental laboratories: mechanical characterization of unidirectional composites, low cycle fatigue behaviour, fracture toughness.

In italic: Description and contents of the course Modeling of Mechanical Behaviour of Materials B (6CFU - 5 hours/week)

The exam includes an oral test covering the full program of the course. A short report on numerical and experimental laboratories is compulsory.

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