COPPER-BASED SURFACE-ENGINEERED MATERIALS FOR BIOMEDICAL AND CATALYTIC APPLICATIONS

Author

Carlos Eduardo Blank Moncada, Virginia Commonwealth UniversityFollow

Author ORCID Identifier

0009-0007-4906-5189

Defense Date

2025

Document Type

Dissertation

Degree Name

Doctor of Philosophy

Department

Mechanical and Nuclear Engineering

First Advisor

Dr. Carlos E. Castano

Abstract

This dissertation investigates the structure-property relationships in surface-engineered Ti-Cu sintered alloys for biomedical implants and Cu-Cr-O catalysts for chemical synthesis. Advanced multiscale characterization was employed to elucidate the mechanisms linking processing history to functional performance in these distinct material systems.

In the biomedical study, Ti-Cu alloys were fabricated from core-shell feedstock powders synthesized via high-power impulse magnetron sputtering (HiPIMS). Compared to blended elemental approaches, the core-shell approach yielded higher density and more uniform copper distribution after vacuum high-heating-rate sintering. These microstructural improvements significantly enhanced hardness and Young’s modulus while maintaining corrosion resistance comparable to commercially pure titanium. However, copper loss during rapid sintering limited antibacterial efficacy at short exposure times, identifying copper retention as a critical parameter for future optimization.

In the catalytic study, the thermal and chemical stability of copper chromite (CuCr₂O₄) was analyzed under reducing conditions. In situ X-ray diffraction and XPS revealed that the reduction of Cu²⁺ to active Cu⁰/Cu⁺ species initiates between 150 and 200 °C. A stable Cr³⁺ framework accommodates this reduction and redistribution of copper active sites. Additionally, the transient formation of the delafossite CuCrO₂ phase was observed at intermediate temperatures, experimentally validating theoretical predictions regarding its electronic stability.

Collectively, this research establishes the microstructural and chemical mechanisms governing these systems. By integrating structural, mechanical, and redox analyses, this work provides rigorous design principles for optimizing engineered metallic biomaterials and oxide catalysts for demanding environments.

Rights

© The Author

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

12-17-2025