Vlad Podgurschi
PhD Student - Imperial College, London
Project Title: Iodine stress-corrosion cracking (I-SCC) of zirconium
Vlad Podgurschi completed his MEng in Materials with Nuclear Engineering at Imperial College London in 2016, and is continuing his research on nuclear materials through his PhD. The aims of this PhD project are to investigate the effects that iodine and other halogens have on the stress-corrosion cracking process in pressurised water reactor (PWR) fuels. The exact chemistry of the attacking species is not yet known, and additionally, there is debate surrounding the role of oxygen in the presence of iodine and whether it inhibits or enhances the I-SCC process. The project examines the fracture process of Zirconium and how iodine and oxygen affect that process.
Existing techniques of investigating fracture processes use either empirical potentials for describing the interaction between limited types of atoms in large systems or use quantum mechanics techniques that allow chemical accuracy but are limited to very small systems. Using a recently developed hybrid quantum mechanics molecular mechanics technique, the investigation of large systems is possible while maintaining high chemical accuracy at crack tips via density functional theory (DFT) calculations. Various types of fracture simulations including molecular statics, molecular dynamics and nudged elastic band simulations are performed in order to determine what the effect of iodine is on the process.