Date on Master's Thesis/Doctoral Dissertation

5-2023

Document Type

Master's Thesis

Degree Name

M. Eng.

Cooperating University

University of Louisville

Department

Chemical Engineering

Committee Chair

Gupta, Gautam

Committee Member

Kunal, Kate

Committee Member

Jaeger, Vance

Author's Keywords

Corrosion; Additive-Manufacturing; Stainless-Steel; Copper; Electrochemistry; Fused-Deposition Modeling

Abstract

The purpose of this study was to investigate and compare the corrosion mechanisms between wrought and additive-manufactured (3D-printed) copper and stainless steel. The experimental procedure consisted of measuring the open circuit potential, electrochemical impedance spectroscopy, linear sweep voltammetry, Tafel analysis, surface topology, and scanning electron microscopy for each metal within salt water, tap water, sulfuric acid, and synthetic body fluid (excluding copper in synthetic body fluid).

Overall, printed stainless steel was more corrosion-resistant than wrought stainless steel in tap water and synthetic body fluid based on OCP, LSV, and surface topology results. Additionally, printed copper was more corrosion-resistant than wrought copper in tap water and 0.5 M sulfuric acid. Thus, printed metals seem to resist corrosion more than their wrought versions in tap water only.

Based on EIS results of stainless steel, printed stainless steel was found to be more corrosion-resistant than wrought stainless steel in only synthetic body fluid. Although kinetics data shows that printed stainless steel is more corrosion-resistant than wrought in tap water, both corrode at similar rates, so this conclusion may be overlooked. On average, printed and wrought 17-4PH stainless steel corroded the fastest in 0.5 M sulfuric acid, followed by synthetic body fluid, then salt water, and finally tap water. Stainless steel exhibited complete pitting corrosion in salt water and synthetic body fluid and experienced uniform (and partial uniform) corrosion in tap water and sulfuric acid.

Based on EIS results of copper, printed copper was more corrosion-resistant than wrought copper in tap water. Although kinetics data supports that printed copper is more corrosion-resistant than wrought copper in salt water and sulfuric acid, both corrode at similar rates in both cases. Therefore, this conclusion can also be neglected. Printed and wrought copper corroded the fastest in 0.5 M sulfuric acid, followed by salt water, then tap water. Copper exhibited uniform (and partial uniform) corrosion in tap water, salt water, and 0.5 M sulfuric acid.

Share

COinS