Experimental Micromechanical Characterisation Group

Sarah Hiew Sze Kei (Research Postgraduate)

Co-supervised by Dr Stella Pedrazzini, Dr Thibaut Dessolier and Willem Maarten van Haaften

In collaboration with Shell Global Solutions International B.V.

Thermo-Mechanical Control Process (TMCP) steels were used as pipeline structures within the oil and natural gas industry due to its high strength, toughness and weldability. Despite being long accepted for operation, there is a risk that TMCP steels can be susceptible to sulphide stress cracking (SSC) in the presence of aqueous H2S environment, leading to premature failure. This project aims to study the mechanistic behaviour of TMCP steel under such low pH environment using an in-situ cathodic charging rig designed in-house. Results obtained from the various crack monitoring techniques used during the experiment will be corelated with findings obtained from the post-mortem microstructural analysis. Finally, these observations will be assessed together with those obtained using the autoclave H2S gaseous method.

Mitra Ashrafi Golshan (Research Postgraduate)

Co-supervised by Dr Katharina Marquardt 

In collaboration with Rolls-Royce plc

Member of Advanced Characterisation of Materials CDT

In this project, two off materials will be studied; Titanium-64 alloy and Inconel-718 superalloy, which are widely used in aerospace applications. I will develop characterisation methods for the signature of damage and failure of aero-engine components using electron backscatter diffraction (EBSD). Additionally, during this study, the experimental result will be correlated with other methods, including electron channelling contrast image (ECCI) and kernel average misorientation (KAM) mapping to understand deformation and relate dislocation structures to crack path and impact of fatigue in the two materials.

Yusen Wang (Research Postgraduate)

Co-supervised by Dr Christopher Gourlay

Lead-free solders are used as interconnects in many electronic devices. At room temperature they are at a significant fraction of their melting temperature (>0.6Tm) and can fail due to creep. Furthermore, when devices are dropped they can be deformed at very high strain rate. In this project, I am using variable temperature and variable strain rate macro- and micro-mechanical testing to understanding the role of intermetallic compounds found in lead free solders.