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.

Dielectric Materials

This teaching and learning package will introduce you to the properties and uses of dielectric materials.

Diffraction and Imaging

A brief summary of diffraction and imaging using an optical system.

Dislocation Energetics

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

Introduction To Dislocations

Dislocations are crucially important in determining the mechanical behaviour of materials. This teaching and learning package provides an introduction to dislocations and their motion through a crystal. A 'bubble raft' model is used to demonstrate some of the features of dislocations and other lattice defects. Some methods for observing real dislocations in materials are examined.

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.

Electromigration

Electromigration is an ever-increasing problem as integrated circuits are pushed towards further miniaturization. The theory of the phenomenon is explained, including electromigration-induced failure and how it has been and can be minimized.

Epitaxial Growth

This TLP enables you to explore the way in which perfect thin crystalline layers are deposited epitaxially (i.e. in the same crystal orientation) on semiconductor substrates. This is the way many electronic and opto-electronic devices are now fabricated using techniques such as molecular beam epitaxy (MBE).

Ferroelectric Materials

Ferroelectrics have been used in real-world applications for a small number of decades, most notably for non-volatile data storage. For example, they have been used in a Sony Playstation and Japanese railway cards.

Ferromagnetic Materials

How many ferromagnets do you think you own? Maybe many more than you realise. Ferromagnetic materials lie at the heart not just of the humble compass, but also of many loudspeakers and of computer memory. This teaching and learning package outlines the microscopic basis of magnetism and some of the conquences of ferromagnetic order in real materials.

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.

The Jominy End Quench Test

Discusses the aims, method and use of results of a test for the hardenability of steel.

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.

Phase Diagrams and Solidification

Phase diagrams are a useful tool in metallurgy and other branches of materials science. They show the mixture of phases present in thermodynamic equilibrium. This teaching and learning package looks at the theory behind phase diagrams, and ways of constructing them, before running through an experimental procedure, and presenting the results which can be obtained.

Introduction To Photoelasticity

This tutorial is based on lab work within the Department of Materials Science and Metallurgy at the University of Cambridge. The tutorial provides an introduction to the topic of photoelasticity and preparation for lab work. Photographs illustrate many features of birefringence in polymers under polarised light.

Physical Vapour Deposition of Thin Films

This TLP aims to look at Physical Vapour Deposition (PVD) as a method to apply thin films. It covers evaporation and sputtering, and then moves on to look at shadowing.

Piezoelectric Materials

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

Pyroelectric Materials

Pyroelectric materials are found in almost every home, in the form of intrusion detectors and other devices, and this TLP will consider how they work, and what the most common ones are made of.

Introduction To Semiconductors

This teaching and learning package provides a very basic introduction to semiconductors. These materials are essential to the operation of solid state electronic devices.

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.

Superconductivity

Electrons in pairs? Levitating trains? Superconductivity - the combination of lossless electrical conduction and the ability of a material to expel a magnetic field - is a property that excites interest in fundamental science whilst offering tantalising prospects for a range of applications. In this teaching and learning package (TLP), we trace the history of superconductivity, outline some fundamental properties of superconductors, and describe current and potential applications of materials with this unusual property.

Superelasticity and Shape Memory Alloys

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

Thermal Expansion and the Bi-material Strip

This teaching and learning package (TLP) is based on lab work in the Department of Materials Science and Metallurgy at the University of Cambridge. The TLP provides an introduction to the topic of thermal expansion, and its application, together with the different stiffness of materials, in the bi-material strip. The TLP leads you through experiments to measure Youngs Modulus from the deflection of a cantilever beam, and to estimate the boiling temperature of nitrogen and the expansivity of a polycarbonate material from the curvature of a bi-material strip immersed in liquid nitrogen.

X-ray Diffraction Techniques

This teaching & learning package provides an introduction to X-ray diffraction. It describes the main crystallographic information that can be obtained and experimental methods most commonly used.