PhD Studentship (Sponsored by BP) – Mechanism of hydrogen generation and its ingress in steels
It has been known for over a century that hydrogen at ambient temperatures can cause hydrogen embrittlement of high strength steels which can lead to failures. As hydrogen can be taken up by steels during its processing, such as welding, cutting, annealing, pickling, galvanising, and also during service due to corrosion or cathodic protection, it is also important to understand the ability of the environment to generate hydrogen (where hydrogen is not initially present) and the ability of steel to absorb hydrogen. In addition, it is also crucial to measure hydrogen diffusion and its uptake in steel as sensitively as possible.
During cathodic protection, hydrogen is generated at the steel surface (which is made the cathode). If the generated hydrogen enters the steel, hydrogen embrittlement can occur. Thus, understanding the effect of environment on the amount of hydrogen generated is important. In addition to the applied potential, the environment such as the presence of dissolved oxygen and temperature can play an important role. As the cathodic reaction takes place on the surface of the cathode the presence of surface asperities and, defects may also play a secondary role. The increase in the effective surface area in contact with the environment is likely to increase the amount of hydrogen generated. In addition, understanding the mechanism of diffusion of hydrogen and corresponding trapping parameters in several commercial carbon steels and their weldments is an important objective. To understand the effect of the variables discussed above this project will investigate the effect of the following on the amount of hydrogen generated:
• Applied external potential
• Environment (H2S, Oxygen, Temperature etc.)
• Surface condition such as roughness
• The effect of temperature on the diffusion coefficient of ferritic steel parent and welds
• The effect of specimen thickness on the measured diffusion coefficient values
• Attempt to correlate the diffusion coefficient to the steel microstructure
About the sponsor
As one of the world’s leading oil and gas companies, BP operates in some of the deepest waters in the world, where reservoirs can be thousands of feet below the seabed, and with hot, highly pressurised corrosive fluids. In such testing environments, the management of structural integrity is of critical importance. BP are interested in new approaches and technologies that lead to improved safety, more effective and more cost-efficient. For more information about BP, its activities and latest news visit our website: www.bp.com
Projects will be based at NSIRC, a state-of-the-art postgraduate facility established and managed by structural integrity specialist TWI in Cambridge. NSIRC is sponsored by TWI, BP and Lloyd’s Register Foundation. For more information about The National Structural Integrity Research Centre, visit www.nsirc.co.uk
Candidates should have a relevant degree at 2.1 minimum, or an equivalent overseas degree in Chemistry, Applied Chemistry, Metallurgy, Mechanical/Structural Engineering, Material Science or Physics. Candidates with suitable work experience and strong capacity in analytical 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 BP, TWI and academic partners. The studentship will provide successful Home/EU students with a stipend of £16k/year (equivalent to approx. £20k tax free salary) and will cover the cost of tuition fees. Overseas applicants are welcome to apply, with total funding capped at £20k/year.