MSE Seminar Series presents:

Corrosion Behavior of Additively Manufactured Al6061 Alloys

Erica Murray
Louisiana Tech University

Abstract
The corrosion behavior of Al6061 alloy samples fabricated by additive friction stir deposition (AFS-D) was evaluated. AFS-D is a rapid, scalable solid-state process also known as MELD additive manufacturing. In this study, electrochemical corrosion tests of AFS-D Al6061 alloy samples were performed by exposing the alloy surface to 3.5% NaCl solution while measuring the impedance response, polarization resistance, and cyclic polarization behavior. As surface characteristics can significantly impact corrosion, the surfaces of Al6061 samples that were perpendicular and parallel to the build direction were tested. Analysis of the surface microstructure relative to the electrochemical corrosion behavior indicated anisotropic material properties that were related to the build direction. The extensive material flow and mixing occurring during deposition seemed to promote a more homogeneous particle distribution with fewer flaws over the Al6061 alloy surface that was perpendicular to the build direction, thereby contributing to greater corrosion resistance. Characteristics of the passive oxide layer, the corrosion potential, corrosion current (i.e., corrosion rate), tendency for pitting, as well as passivation/repassivation kinetics were determined from analysis of the electrochemical corrosion data.

Bio
Dr. Erica Perry Murray is a Research Associate Professor at the Institute for Micromanufacturing at Louisiana Tech University. Dr. Murray applies electrochemical techniques to study the corrosion characteristics of complex metal alloys fabricated by various additive manufacturing methods; and explores the electrochemical response characteristics of electroceramic materials relevant to gas sensors and solid oxide fuel cells. Prior to joining Louisiana Tech, Dr. Murray worked as a Research Scientist in the Physical and Environmental Sciences Department in the Research and Innovation Center at Ford Motor Company in Dearborn, Michigan. The research in Dr. Murray’s lab has primarily been supported by the National Science Foundation and NASA, as well as industrial partnerships. Her research has attracted collaborative research activities with Ford Motor Company, Cummins, MELD Manufacturing Corporation, Lockheed Martin, and Trelleborg Applied Technologies. In addition to academic research, Dr. Murray has created and led various STEM/STEAM activities for the Boys and Girls Club of North Central Louisiana, Paul E. Slaton Headstart Program, and local elementary schools.