Fully funded PhD positions available @ Loughborough University, UK

Topic: Towards zero prototyping in ceramic component design

This project is aimed at transforming the manufacturing of products using ceramics and ceramic-based composite materials to allow mechanical properties to be tailored for the desired performance. The current approach involves extensive use of trial-and-error methods with empirical modelling approaches. The proposed project seeks to replace this approach with a robust framework involving the use of novel modelling and simulation techniques, enabling product and process designers and manufacturers to eliminate the need for physical prototypes. Such an approach will improve the overall design process, speed up the design cycle, reduce costs and create better designs.

Application of ceramics in essential products like body/vehicle armours, engines, and prosthetics is critical for maximising their performance, but much less understood in comparison to metallic materials, signifying opportunities for growth in the future. Some interesting observations made from post-ballistic testing analysis of recovered fragments of SiC ceramic material shows dominant plastic flow on the fracture surfaces. This demonstrates the underlying complexity of deformation mechanisms in a nominally brittle material.

The project aims to achieve a paradigm for zero prototyping at the component level. To achieve this an in-depth knowledge of material behaviour is required ranging from the smallest temporal and spatial lengths scales to the largest. Our team of academics consists of modelling experts who will help develop physics based models of material response from the smallest length scales to the largest. We also have characterisation and material processing experts who will study the influence of material processing and manufacturing techniques on the mechanical response of components and validate the models. 

Number of studentships available: 4

Deadline: 16 June 2014 

Projects:

Project 1: Nano-mechanics: the fundamental nature of deformation on the smallest scale will
be investigated with the aid of atomic scale simulations. This study will help
elucidate the various mechanisms of plastic deformation and fracture in these brittle
materials.

Project 2:
Micro-mechanics: The interaction between dislocation dynamics
and material microstructure is the major source for heterogeneous plasticity
and internal stress concentration, leading to initiation and growth of cracks
and failure. To physically simulate the material plasticity behaviour, a
three-dimensional discrete-dislocation-dynamics approach will be developed to
simulate the interaction between dislocations and grain microstructures
(including defects). Computational simulations will be validated against local
deformation measurements and post-mortem microscopic examinations in project 4.
Core dislocation properties
(nucleation, multiplication, glide, annihilation, climb and cross-slip) and
short-range  dislocation interactions
(formation of jogs, junctions and dipoles) will be modelled based on the critical
insights provided in project 1.

Project 3:
Meso-Macro Continuum mechanics: Typically most, if
not all, functional components belong in the meso-to-macro length scale. Thus
it becomes imperative to develop numerical models, which are computationally
efficient at the same time being physically relevant. In other words, these
models should account for the cumulative response of the underlying
microstructure without having to resolve them individually. Coarse-graining
techniques will be used to develop these models from the descriptions in
projects 1 & 2.

Project 4:
Materials processing and characterisation of deformation mechanisms: The effect of processing routes on the grain structure and defect
populations in ceramics will be studied to provide input into project 2.
Deformation processes in these materials will be studied in details with
advanced microstructural and mechanical characterisation techniques in
conjunction with the three modelling projects to validate the model outcomes at
different length scales.

See details: 

http://www.jobs.ac.uk/job/AIA409/phd-studentships/

http://www.lboro.ac.uk/services/graduateschool/funding-prospective/graduate-school-studentships/