Abstract

This dissertation investigates the impact of high pressure and high temperature on the nitridation phenomenon in various superalloys by exposure to NH₃. This aim is achieved through the design and performance of unique experimental reactors for studying material nitridation under extreme NH₃ conditions over extended durations. The selection and preparation of materials for nitridation studies, primarily Ni-based alloys, are discussed, along with the fine-tuning of system components and parameters to maximize the nitriding potential on specimen surfaces. Following the experimental campaign, insights into material interactions in aggressive environments are provided. The analysis includes weight change, corrosion rate, and corrosion resistance calculations, along with cross-sectional techniques such as optical imaging, scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) of metal samples. These outcomes are expected to contribute to the development of material rankings to assist decision-makers in the energy transition process at an industrial scale.

Biography

Nicole Laws is currently a Ph.D. candidate in the Mechanical Engineering Program under the supervision of Professor William Roberts. She received her B.Sc. in Mechanical Engineering from Brigham Young University, Utah, USA in 2018, and her M.Sc. in Mechanical Engineering from KAUST in 2020. Her Ph.D. research focuses on material degradation studies under high-pressure, high-temperature ammonia environments.