Dissemination of IT for the Promotion of Materials Science (DoITPoMS)

DoITPoMS TLP Library

TLP Library

Teaching and learning packages (TLPs) are self-contained, interactive resources, each focusing on one area of Materials Science.

TLPs containing HTML5 animations/simulations are labelled with the tag . We have found that often the HTML5 animations render better in Microsoft Edge, so if your favourite browser does not work very well with them, please try an alternative.

Atomic Scale Structure of Materials

This teaching and learning package provides an introduction to crystalline, polycrystalline and amorphous solids, and how the atomic-level structure has radical consequences for some of the properties of the material. It introduces the use of polarised light to examine the optical properties of materials, and shows how a variety of simple models can be used to visualise important features of the microstructure of materials.

Bending and Torsion of Beams

This teaching and learning package provides an introduction to the mechanics of beam bending and torsion, looking particularly at the bending of cantilever and free-standing beams and the torsion of cylindrical bars.

Brittle Fracture

What determines when a material will break, and whether failure will be catastrophic or more gradual. Cracking is controlled by the energy changes that occur - it is not the stress at the crack tip that is important..

Coating Mechanics

This TLP should provide some insights into the mechanics of bi-layer (coating on substrate) systems. It covers the concept of a misfit strain and the way in which equilibrium is established after its introduction, including the creation of curvature. The differences between "thin" and "thick" coating cases are explained.

Creep Deformation of Metals

Creep is a major concern, since it can cause materials to progressively deform, and possibly to fail, under applied stresses below their yield stress. This is particularly likely at elevated temperatures. In this package, the main mechanisms of creep are outlined and some analytical expressions presented that are used to represent its progression. Testing procedures are described, covering both simple uniaxial loading and more complex test geometries. It is shown how creep characteristics can be inferred from the outcome of such tests, requiring in some cases numerical (finite element) modelling of the process. Information is also presented about the design of highly creep-resistant materials.

Crystallinity in Polymers

An understanding of polymer crystallinity is important because the mechanical properties of crystalline polymers are different from those of amorphous polymers. Polymer crystals are much stiffer and stronger than amorphous regions of polymer.

Dislocation Energetics

This teaching and learning package (TLP) uses an atomistic model of the misfit energy to predict dislocation width and Peierls stress.

Elasticity in Biological Materials

This teaching and learning package (TLP) discusses the elasticity of biological materials. Whilst some show Hookean elasticity, the vast majority do not. Non-linear elasticity is considered, in particular J-shaped and S-shaped curves. Viscoelasticity is also discussed, using hair and spiders' silk as examples.

The Glass Transition in Polymers

This teaching and learning package is based on a lecture demonstrations used within the Department of Materials Science and Metallurgy at the University of Cambridge. The package is aimed at first year undergraduate Materials Science students and focuses on the glass transition in polymers.

Mechanical Testing of Metals

This teaching and learning package (TLP) introduces the basic mechanics involved in mechanical testing of metals, first outlining the meaning of deviatoric and hydrostatic stresses and strains, followed by definitions of true and nominal values and then covering the idea of constitutive laws that characterise the development of plastic deformation. The issues involved in carrying out conventional uniaxial (tensile and compressive) tests, and interpreting experimental outcomes, are then described. Finally, hardness testing is explained, followed by the development of a related technique involving indentation testing that allows full stress-strain curves to be obtained. All of the analyses are based on a continuum treatment of plastic deformation, with extensive numerical modelling, using the Finite Element Method (FEM).

Mechanics of Fibre-reinforced Composites

This teaching and learning package (TLP) gives an introduction to the nature of fibre-reinforced composite materials and their basic mechanical characteristics.

Mechanisms of Plasticity

This TLP should provide some insights into the plasticity of crystals. It covers some of the important concepts in single-crystals such as Frank-Read source, Lomer locks, climb and cross-slip, and their roles in forest hardening. In addition, grain boundary hardening in poly-crystals is also explained.

Optimisation of Materials Properties in Living Systems

This teaching and learning package discusses the uses of merit indices in conjunction with materials-selection maps focusing on biomaterials. The derivation of merit indices is discussed and biological examples are shown.

Piezoelectric Materials

This teaching and learning package (TLP) provides an introduction to piezoelectric materials.

Raman Spectroscopy

An introduction to the analysis of materials and chemicals by the Raman scattering of light.

Slip in Single Crystals

This teaching and learning package explains how plastic deformation of materials occurs through the mechanism of slip. Slip involves dislocation glide on particular slip planes. The geometry of slip is explained, and electron microscopy techniques are used to show slip occurring in single crystals of cadmium.

The Stiffness of Rubber

This teaching and learning package is based on two experiments which demonstrate the behaviour of rubber under tension. The first displays the unusual behaviour of a rubber strip when heated under tension; the second considers the behaviour of a rubber membrane under tension. In both cases the behaviour is considered theoretically in terms of the molecular structure of rubber and the thermodynamic entropy changes involved.

Stress Analysis and Mohr's Circle

This teaching and learning package provides an introduction to the theory of metal forming. It discusses how stress and strain can be presented as tensors, and ways of identifying the principal stresses. Suitable yield criteria to treat metals and non-metals are also presented.

The Structure and Mechanical Behaviour of Wood

This teaching and learning package discusses the structure of wood, focusing on the structure of the tree trunk and the differences between hardwoods and softwoods. The stiffness and strength of different types of wood are discussed, and the different behaviour of wood when wet is investigated.

Structure of Bone and Implant Materials

This teaching and learning package (TLP) describes the structure of bone from the macro-scale to the micro-scale and considers its description as a biological composite. The structure of hip replacements is described and common implant materials are discussed in relation to the mechanical properties of bone.

Superelasticity and Shape Memory Alloys

This teaching and learning package (TLP) introduces the phenomena of superelasticity and the shape memory effect.