Development of fracture toughness testing techniques for non-sharp defects

The shape of defects and in particular their local topology, e.g. flaw tip acuity, are known to have a significant impact on the ability of materials to withstand load. Studies on cleavage fracture, ductile initiation and tearing and on the type of fracture mechanism have shown the beneficial effect of defect bluntness. A critical factor for achieving a complete characterisation of bluntness effect of failure is the development of fracture testing guidance for notched specimens.
It has been observed that cleavage fracture and ductile tearing from notch tips is more complex than from fatigue pre-cracked standard specimens. The measurement and definition of initiation and crack growth is not as straightforward for notched specimens, i.e. short cracks have been observed to be in competition on different planes. In addition, minimum thickness requirements specified in fracture toughness testing standards for ensuring high constraint conditions dominate are only applicable to fatigue pre-cracked specimens.
This is an exciting opportunity to work in a highly motivated and vibrant research-intensive group as well as spending time at a leading industrial institute in the field, TWI Ltd. In collaboration with another PhD student, you will be working towards the development of notch fracture mechanics based testing protocols. Finite element modelling and laboratory experience is desired although not essential. By engaging with this group, you will develop unique skills in structural integrity and damage mechanisms (fracture, fatigue, plastic collapse) in both an academic (UoB) and industrial environment (TWI).