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.

Introduction To Anisotropy

It is common in basic analysis to treat bulk materials as isotropic - their properties are independent of the direction in which they are measured. However the atomic scale structure can result in properties that vary with direction. This teaching and learning package (TLP) looks into typical examples of such anisotropy and gives a brief mathematical look into modelling the behaviour.

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..

Casting

This TLP introduces a number of important processes through which metallic items can be fabricated from molten metal. As well as detailing the practical aspects of these manufacturing processes, attention is given to the important parameters which determine the microstructure of the finished items.

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.

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.

Diffusion

An introduction to the mechanisms and driving forces of diffusion, and some of the processes in which it is observed.

Dislocation Energetics

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

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).

Introduction to Mechanical Properties of Materials

This teaching and learning package (TLP) introduces mechanical properties of materials, starting from a stress–strain curve and exploring both elastic behaviour (e.g., Hooke's law) and plastic behaviour (e.g., slip, creep).

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).

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.

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.

Polymer Basics

This teaching and learning package is an introduction to the basic concepts of polymer science. It includes molecular structure, synthesis and tests for identification.

Solidification of Alloys

This teaching and learning package (TLP) is an introduction to how solute affects the solidification of metallic alloys.

The Stereographic Projection

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

Tensors in Materials Science

This TLP offers an introduction to the mathematics of tensors rather than the intricacies of their applications. Its aims are to familiarise the learner with tensor notation, how they can be constructed and how they can be manipulated to give numerical answers to problems.

Toughening of Materials

The purpose of this Teaching and Learning Package is to provide an insight into the methods used to toughen brittle materials.

Tribology - the friction and wear of materials

Consideration of the behaviour of surfaces in contact with one another leads to the subject of tribology ? the study of the friction, lubrication and wear of materials.