PhD Studentship (Sponsored by Lloyds Register Foundation) – Crack Tip Constraint in Typical High Strength Steel Components in Arctic Conditions (NSIRC 183)
High strength steel structures in arctic conditions are prone to brittle fracture, due to the complications arising from reduced fracture toughness of steels at low temperatures, exacerbated by the negative effect of thick sections, which can contribute to high crack-tip constraint and a high probability of fracture initiation.
Brittle fractures are a catastrophic failure mode, which can result in global failure of the structure, irreparable damage, and potentially loss of life. An improvement in the methods used to quantify the effects that increase the risk of brittle fracture is therefore desirable.
A good understanding of the structural behaviour of high strength steels in various applications, particularly in arctic environments such as offshore, lifting appliances, pipeline, bridges and buildings etc. is extremely important. Improved knowledge of the conservatism or otherwise of the standard assessment methods of structural integrity and the design codes used for the high strength steels that are evolved from lower grade steels is desirable.
The proposed project concerns an investigation into typical high strength steels used in arctic environments under conditions of loss of crack-tip constraint. The loss of crack-tip constraint is expected to counteract the negative effects of thick sections and arctic temperatures on fracture toughness, and so quantifying it is extremely useful. The fitness-for-service standards e.g. BS 7910, include methods to account for crack-tip constraint, but these methods are not fully developed, and would benefit from refinement for these applications.
The project will include mechanical testing under appropriate conditions (with consideration of the effect of temperature, loading rate, geometry, constraint etc.), to support a parametric fitness-for-service assessment of typical components, supplemented by numerical modelling. This work will inform the assessment of structures in arctic conditions by providing revised advice for high strength steels.
There is the potential for any research developed in the course of this project to pave the way for new rules and advice to be included in guidance documents or standards for high strength steels.
About Industrial Sponsor
The Lloyd’s Register Foundation funds the advancement of engineer-related education and research and supports work that enhances safety of life at sea, on land and in the air, because life matters. Lloyd’s Register Foundation is partly funded by the profits of their trading arm Lloyd’s Register Group Limited, a global engineering, technical and business services organisation.
NSIRC is a state-of-the-art postgraduate engineering facility established and managed by structural integrity specialist TWI, working closely with, top UK and International Universities and a number of leading industrial partners. NSIRC aims to deliver cutting edge research and highly qualified personnel to its key industrial partners.
Candidates should have a relevant degree at 2.1 minimum, or an equivalent overseas degree in engineering or materials science. Candidates with suitable work experience and strong capacity in numerical modelling and experimental skills are particularly welcome to apply. Overseas applicants should also submit IELTS results (minimum 6.5) if applicable.
This project is funded by Lloyds Register Foundation, TWI and academic partners. The studentship will provide successful Home/EU students with a stipend of £16k/year and will cover the cost of tuition fees. Overseas applicants are welcome to apply, with total funding capped at £24k/year.