Research Studentship in Impact Failure of Amorphous Polymers - - Department of Engineering Science, University of Oxford

3-year DPhil studentship 

Supervisors: Prof Clive Siviour

Ballistic impact is a complex event that induces multiple modes of deformation, is influenced by both material and structural responses, and excites a very wide range of strain rates. In cases where brittle failure is induced, effects of processing history, such as flaws and residual stresses, also play a significant role in the final response.

There is a need, therefore, to produce material models that can be used in computer simulations of ballistic events, and which contain enough physical understanding of deformation and failure behaviour to provide insight into how processing affects the final response. This project will address this problem through a combination of experimental development at the University of Oxford, and modelling at the University of Nottingham, using polycarbonate as a model material. The ultimate goal is to provide models to understand and simulate phenomena observed in polymers under impact, and the effect of different polymer histories on these phenomena. This builds on current collaborative research, in which a new rate and temperature dependent constitutive model has been developed, by focusing on understanding the basic polymer physics that drives fracture.

Oxford will lead the experimental program. You will develop methods for measuring failure parameters under impact. In particular, you will focus on the use of advanced high speed imaging techniques to better measure the deformation fields around failure sites, which will themselves be controlled through bespoke specimen design. You will also use time-temperature superposition as a means both to explore the effects of polymer behaviour on fracture and also as a predictive tool, capturing the significant rate and temperature dependence of the materials. You will also explore the effect of different thermal and surface treatments on the observed response, including the application of residual stresses.

Eligibility

This studentship is fully funded at the Home level (fees plus stipend) by the US Army.

Award Value

Course fees are covered at the level set for UK students (c. £8960 p.a.). The stipend (tax-free maintenance grant) is c. £20,000 p.a. for the first year, and at least this amount for a further two years.

Candidate Requirements

Prospective candidates will be judged according to how well they meet the following criteria:

• A first-class honours degree (or equivalent) in Physics, Engineering, or Materials Science
• Excellent written and spoken communication skills in English
• Interest in properties of polymers, in particular under dynamic loading

The following skills are also highly desirable:

• Ability to program in Matlab, Python, or similar
• Strong laboratory-based skills
• Experience in materials testing at high strain rates or under impact

Applicants with a good 2.1 degree are also encouraged to apply if they can demonstrate excellent laboratory skills through previous research or an undergraduate project.

 

Application Procedure

Candidates must submit a graduate application form and are expected to meet the graduate admissions criteria. Details are available on the course page of the University website. Before going through this process, applicants are strongly encouraged to make informal enquiries, which should be addressed to Prof Clive Siviour (clive.siviour@eng.ox.ac.uk).

Please quote 24ENGMM_CS2 in all correspondence and in your graduate application.

Application deadline: noon on 08 July 2024

Start date: October 2024