Irradiation effects on geopolymer and additively manufactured 316H stainless steel and porosity in equine hoof wall
type: CreativeWork
description: This Ph.D. dissertation research investigated three classes of materials designed for extreme environments. They include metakaolin-based geopolymers for nuclear shielding, additively manufactured (AM) 316H stainless steel (SS) for radiation resistance, and equine hoof walls serving as bioinspiration for impact-resistant materials designs. First, I explored a potassium-based geopolymer implanted with Ti+ ions to simulate neutron irradiation as a concrete alternative for nuclear facilities. Post-irradiation, the geopolymer showed a 90% increase in microhardness, a 46% rise in reduced modulus, and a 23% decrease in contact depth. Surface cracking was observed, attributed to ion implantation and reduced water content, highlighting its potential for shielding applications with further optimization. Next, we studied the irradiation response of AM 316H SS, produced via laser powder bed fusion, compared to conventionally manufactured SS under simulated irradiation conditions using 0.5 MeV H+ ions. Multiscale characterization showed AM SS exhibited higher initial dislocation densities, reduced microstrain at lower doses (0.6 dpa), and more stable mechanical behavior under irradiation than conventional SS. Microhardness testing revealed a gradual response in AM SS, while tensile tests indicated reduced hardening and strength. The surface analysis highlighted distinct pore morphologies and stable elemental composition in AM SS, contrasting the significant surface deterioration in conventional SS. These findings demonstrate AM 316H SS’s superior microhardness, microstructural integrity, and radiation resistance, underscoring its suitability for irradiated environments. Molecular dynamics simulations allowed us to explore the influence of porous microstructures on AM 316H SS’s radiation resistance. By investigating varying pore configurations (1 to 30,720 pores) and primary knock-on atom (PKA) energies (5, 10, and 15 keV), this modeling revealed that defect numbers increased si…
abstract: This Ph.D. dissertation research investigated three classes of materials designed for extreme environments. They include metakaolin-based geopolymers for nuclear shielding, additively manufactured (AM) 316H stainless steel (SS) for radiation resistance, and equine hoof walls serving as bioinspiration for impact-resistant materials designs. First, I explored a potassium-based geopolymer implanted with Ti+ ions to simulate neutron irradiation as a concrete alternative for nuclear facilities. Post-irradiation, the geopolymer showed a 90% increase in microhardness, a 46% rise in reduced modulus, and a 23% decrease in contact depth. Surface cracking was observed, attributed to ion implantation and reduced water content, highlighting its potential for shielding applications with further optimization. Next, we studied the irradiation response of AM 316H SS, produced via laser powder bed fusion, compared to conventionally manufactured SS under simulated irradiation conditions using 0.5 MeV H+ ions. Multiscale characterization showed AM SS exhibited higher initial dislocation densities, reduced microstrain at lower doses (0.6 dpa), and more stable mechanical behavior under irradiation than conventional SS. Microhardness testing revealed a gradual response in AM SS, while tensile tests indicated reduced hardening and strength. The surface analysis highlighted distinct pore morphologies and stable elemental composition in AM SS, contrasting the significant surface deterioration in conventional SS. These findings demonstrate AM 316H SS’s superior microhardness, microstructural integrity, and radiation resistance, underscoring its suitability for irradiated environments. Molecular dynamics simulations allowed us to explore the influence of porous microstructures on AM 316H SS’s radiation resistance. By investigating varying pore configurations (1 to 30,720 pores) and primary knock-on atom (PKA) energies (5, 10, and 15 keV), this modeling revealed that defect numbers increased si…
author: Mahrous, Mahmoud A.
language: en
keywords: Extreme environments, radiation resistance, additive manufacturing, molecular dynamics simulations, bioinspired materials, geopolymers, 316H stainless steel, ion irradiation, porous microstructures, multiscale characterization
date published: 2025-12
date modified: 2026-07-22T22:25:07Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois Urbana-Champaign

PropertyValue
property ID: Handle
value: https://hdl.handle.net/2142/132510