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.

Brillouin Zones

This teaching and learning package provides an introduction to Brillouin zones in two and three dimensions and is aimed at developing familiarity with Brillouin Zones. It will not cover any specific applications. Brillouin Zones are particularly useful in understanding the electronic and thermal properties of crystalline solids.

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.

Crystallographic Texture

This teaching and learning package (TLP) introduces the concept of texture in crystalline materials such as common metals and metallic alloys.

Crystallography

Crystalline materials are characterised by a regular atomic structure that repeats itself in all three dimensions. In other words the structure displays translational symmetry.

Diffraction and Imaging

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

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.

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).

Examination of a Manufactured Article

This TLP provides an introduction to the deconstruction and investigation of the materials and processes used in an everyday item or article.

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.

The Jominy End Quench Test

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

Lattice Planes and Miller Indices

This teaching and learning package provides an introduction to the method used to describe planes of atoms in a crystalline material. The practical uses of describing planes of atoms are also addressed.

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).

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.

Powder processing

This teaching and learning package (TLP) provides an introduction to the dynamics of powder particles in fluid streams and relates this background to issues such as the time for which such particles remain suspended in air or water and the likelihood of them striking obstacles in their path. It also presents a description of the main routes by which (ceramic or metallic) powders are converted to solid objects.

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 Stereographic Projection

This TLP covers the use of the Stereographic projection and Wulff nets.

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.