Physics projects for Y3 and Y4 students

Project description

Phase transformations in alloys under heat treatment and deformation

(supervisor: Rudi Winter)

Nature of project: experimental, data analysis

Available to students on full-time physics degree schemes or joint students.

Project description and methodology

Alloys are metals consisting of a mixture of chemical elements. They usually have a heterogeneous microstructure consisting of grains with different composition and/or crystal structure. This microstructure determines material properties such as hardness and ductility. Therefore, processing techniques such as annealing and deformation (folding) target specific microstructures to make alloys with specific properties.

In this project, we will investigate how thermal and mechanical treatments alter the microstructure of steel of a given composition (e.g. mild steel) and how this influences mechanical properties of the alloy.

The core segment of the project will involve making measurements such as taking optical micrographs of polished specimens that have undergone heat and/or mechanical treatment and analysing them quantitatively using image processing software. The information gained should be related to the phase diagram of steel, with the aim of understanding pathways that lead to the formation of the crystalline phases (such as martensite or austenite) detected.

A successful project will develop beyond the above in one/some of the following directions:
This could be extended by taking images by atomic force microscopy (AFM) or scanning electron microscopy (SEM) with chemical information via energy-dispersive x-ray (EDX) detection. These would again be analysed quantitatively using image analysis techniques.

Subject to availability of the instrument, x-ray diffraction (XRD) could be used to demonstrate how different crystalline phases appear and disappear following the various processing methods.

While the core of the project concentrates on a single alloy, it could be extended to look at other types of steel or even different metals.

When considering where to take your project, please bear in mind the time available. It is preferable to do fewer things well than to try many and not get conclusive results on any of them. However, sometimes it is useful to have a couple of strands of investigation in parallel to work on in case delays occur.

This project is only available as a Y3 project.

Please speak to Rudi Winter (ruw) if you consider doing this project.

Initial literature for students:

  1. JD Anderson et al.; Materials Science, Stanley-Thornes (1998), ch.10
  2. WD Callister; Materials Science and Engineering, Wiley (2007), ch.11
  3. http://users.aber.ac.uk/ruw/teach/334/sem.php (lecture notes on microscopy techniques)

Novelty, degree of difficulty and amount of assistance required

This is a project at the interface between science and engineering. It is important that the relationships between a material's structure and its properties are thoroughly investigated and understood. Some of the experimental techniques and image analysis may be new to physics students taking this project, but help is on hand.

Project milestones and deliverables (including timescale)

milestoneto be completed by
set of treatments to be investigated to be defined, based on literature findings and discussion with the mechanical workshop on what can realistically be done hereend of November
set of specimens made and prepared for analysis, initial micrographs takenend of February
image analysis workflow established and testedmid-March
all images analysedEaster

Students taking this project will have to submit a full risk assessment form