Additive Manufacturing: Mechanisms and Mitigation of Aqueous Corrosion and High-temperature Oxidation: Corrosion Behavior of Additively Manufactured Metals and Alloys
Sponsored by: TMS Corrosion and Environmental Effects Committee, TMS: Additive Manufacturing Committee
Program Organizers: Amir Mostafaei, Illinois Institute of Technology; Yashar Behnamian, University of Alberta; Mohsen Mohammadi, University of New Brunswick; Bryan Webler, Carnegie Mellon University; Kinga Unocic, Oak Ridge National Laboratory
Tuesday 8:00 AM
October 11, 2022
Room: 307
Location: David L. Lawrence Convention Center
Session Chair: Amir Mostafaei, Illinois institute of Technology; Bryan Webler, Carnegie Mellon University
8:00 AM
Corrosion Evaluation of Additively Manufactured Al-Cu-X Alloys: Jiheon Jun1; Alex Plotkowski1; Amit Shyam1; J. Haynes1; Yi Feng Su1; 1Oak Ridge National Laboratory
Additively manufactured (AM) Al-Ce-X alloys have potential to be utilized in manufacturing of advanced power train components in future automotive designs. These AM Al-Ce-X alloys exhibit unique microstructures distinguished from cast aluminum alloys with similar compositions, which could alter their aqueous corrosion resistance. To investigate the corrosion behavior of AM Al-Ce-X alloys, electrochemical impedance spectroscopy (EIS) was applied along with anodic and cathodic polarization techniques in 3.5 wt.% NaCl. Corrosion reaction resistance, determined from EIS, as well as anodic and cathodic currents were compared between AM and cast Al-Ce-X alloys for comprehensive corrosion analysis. Microscopic and chemical characterization of pre- and post-corrosion specimens are also underway to identify the microstructural feature(s) associated with corrosion susceptibility in the alloys. This work was supported by U.S. DOE Vehicle Technology Office, Powertrain Materials Core Program.
8:20 AM
Effect of Aging Treatment on Stress Corrosion Cracking Response of Cold Sprayed Al 6061 Alloy: Ryan Cochran1; Shiraz Mujahid1; Aulora Rusk1; YubRaj Paudel1; Marc Pepi2; Peter Czech3; Hongjoo Rhee1; 1Center for Advanced Vehicular Systems at Mississippi State University; 2Army Research Laboratory; 3American Lightweight Materials Manufacturing Innovation Institute
Cold Spray additive manufacturing (CSAM) can generate fully dense, low porosity parts; however, mechanical properties such as stress corrosion cracking (SCC) depend on process parameters like flow rate, deposition velocity and post-deposition treatment. When manufactured using alloys such as Al 6061, CSAM parts exhibit corrosion crack resistance in general, but catastrophic failure can occur in the presence of stress where inter-splat bonding is limited, as reagents dissolve inter-splat boundaries due to the nature of deposits generated with CSAM. This study aims to measure the effects of aging parameters on SCC response in CSAM Al 6061 deposits compared to bulk. Inter-splat behavior was observed to evaluate the influence of precipitate formation on specimen response during SCC testing and determine how aging implemented post-deposition improves bonding and reduces failure at boundary regions.
8:40 AM
Electrochemical Behavior of Additively Manufactured Non-spherical Ti-6Al-4V in Saline Water: Melody Delpazir1; Mohammadreza Asherloo1; Muktesh Paliwal2; Amir Mostafaei1; 1Illinois Institute of Technology; 2Kymera International
Cost-effective, non-spherical Ti-6Al-4V powders produced by hydride-dehydride (HDH) method are processed by laser powder bed fusion (LPBF) for implant applications. It is well-established that the microstructure of the LPBF processed part will considerably affect the corrosion behavior in saline water. Thus, it is vital to conduct a study on the effect of the LPBF process on the microstructure of the as-build and post process heat-treatment parts. The electrochemical behavior is studied in saline solutions of 0.9, 3.5, and 10% NaCl. Grain structure and phase fraction are studied by optical microscopy and electron backscatter diffraction to investigate the correlation between microstructure and post processing on the electrochemical properties upon exposure to corrosive conditions. Evaluating the effect of post heat treatment on corrosion behavior of non-spherical HDH LPBF Ti-6Al-4V printed samples, can sustain the integrity of the newly introduced powders to be replaced with expensive spherical Ti-6Al-4V powders.
9:00 AM
Electrochemical Performance of Additively Manufactured 8620 Low Alloy Steel: Effect of Acetic Acid: Ezazul Haque Sabuz1; Ishraq Shabib1; 1Central Michigan University
As additive manufacturing is gaining attraction within the scientific community due to its capability to produce functional components, new metal powders are being developed for application in different areas. One such powder is 8620 low alloy steel, which has a wide range of use owing to its hardenability and excellent wear resistance. However, structural components e.g., engine crankshaft, camshaft, wrist pin, etc., made from 8620 steel face material degradation in corrosive environments. In this study, electrochemical performance of additively manufactured and wrought 8620 will be investigated via Potentiodynamic Polarization (PD) and Electrochemical Impedance Spectroscopy (EIS) techniques in three concentrations of acetic acid- 5 %, 10%, and 15% in presence of 3.5% NaCl. The characterization of the corroded surface after PD will be conducted via Scanning Electron Microscope (SEM) and Energy Dispersive Spectroscopy (EDS). The understanding obtained from this project can be used to design functional components for the automotive industry.
9:20 AM
Leveraging Additive Manufacturing to Co-design Mechanical Properties and Environmental Resistance: Rishi Pillai1; Rebecca Kurfess1; Yi Feng Su1; QQ Ren1; Soumya Nag1; 1Oak Ridge National Laboratory
Sequential materials design approaches strive to achieve individual physical properties but fail to anticipate the consequences of complex interactions between underlying phenomena, such as environmental degradation and thermomechanical stability, that can substantially impact efficiency, performance and lifecycle requirements. A paradigm shift in these traditional approaches is critically essential to create application-specific hierarchical and multifunctional materials with superior long-term performance for next-generation energy technologies involving extreme environments. In the current work, a new digital manufacturing framework that synergistically integrates established, high-fidelity, physics-based thermo-kinetic models with advanced fabrication techniques will be presented. A novel property graded Ni-based high temperature alloy with the ability to withstand differing environmental attacks exposed to molten halide salts and supercritical CO2 on opposing surfaces is being developed. A coupled thermokinetic model was employed to determine the compositional gradients that will facilitate corrosion resistant surfaces while simultaneously mitigating the corrosion-induced degradation of strengthening phases in the alloy.
9:40 AM
Microstructural Characterization and High-Temperature Oxidation of Laser Powder Bed Fusion Processed Inconel 625: Emily Lewis1; Nick Cruchley2; Moataz Attallah1; Sam Cruchley1; 1University of Birmingham; 2Manufacturing Technology Centre (MTC)
Laser Powder Bed Fused (L-PBF) Inconel 625 (IN625) is a prime candidate for the design of oxidation resistant components at high temperatures. However, existing research into the microstructure and oxidation performance of L-PBF IN625 is limited to short time exposures non-reflective of in-service conditions. This study aims to identify the influence of printed microstructure, post-process heat treatment, and surface modifications on the long-term isothermal oxidation behaviour of L-PBF IN625. Oxidation mechanisms were analysed using mass gain kinetics and oxide film characterisation using scanning electron microscopy, energy dispersive spectroscopy and electron backscatter diffraction. Results showed that printed features such as a dendritic microstructure, microsegregation of Nb and Mo, texture, and surface roughness collectively influenced the oxidation properties. The morphology and distribution of δ-phase (Ni3(Nb,Mo)) precipitate also differed across different heat treatments and surface finishes. Oxidation kinetics were similar to wrought alloy, but more closely followed sub-parabolic and cubic behaviours.