Environmental Degradation of Additively Manufactured Alloys: High Temperature Oxidation and Corrosion, High Temperature Alloys
Sponsored by: TMS Structural Materials Division, TMS: Corrosion and Environmental Effects Committee, TMS: Additive Manufacturing Committee
Program Organizers: Kinga Unocic, Oak Ridge National Laboratory; Jenifer Locke, Ohio State University; Sebastien Dryepondt, Oak Ridge National Laboratory; Michael Kirka, Oak Ridge National Laboratory; Xiaoyuan Lou, Purdue University; Brendy Rincon Troconis, University of Texas at San Antonio; Luke Brewer, University of Alabama
Wednesday 8:30 AM
March 17, 2021
Room: RM 20
Location: TMS2021 Virtual
Session Chair: Kinga Unocic, Oak Ridge National Laboratory; Sebastien Dryepondt, Oak Ridge National Laboratory; Michael Kirka, Oak Ridge National Laboratory
8:30 AM Invited
High Temperature Air Oxidation Behavior of Ni-based Superalloys Processed by Electron Beam Melting (EBM) and Selective Laser Melting (SLM): Marie Romedenne1; Rishi Pillai1; Sebastien Dryepondt1; 1ORNL
Additive manufacturing (AM) aims to complement or replace conventional and costly machining or production processes. While the current focus is on the evaluation of mechanical properties of as-fabricated or heat-treated materials, the oxidation behavior of AM materials is rarely investigated. The oxidation behavior of three Ni-based superalloys fabricated by EBM or SLM was evaluated and compared with the wrought materials. Thermogravimetric analyses and cyclic exposures up to 950 °C for durations up to 5000 h were performed. Alloy microstructure and powder composition were found to strongly influence oxidation behavior and material degradation processes.
9:00 AM Invited
Effect of High-temperature Oxidation on the Fatigue Properties of Inconel 625 Fabricated by Laser Additive Manufacturing: Grace De Leon Nope1; Juan Alvarado-Orozco2; Guofeng Wang1; Brian Gleeson1; 1University of Pittsburgh; 2CIDESI
This study assesses and compares the role of high-temperature oxidation on the high cycle fatigue of wrought and LAM-processed Inconel 625. Previous work demonstrated that different cooling rates in LAM processes impact Nb and Mo segregation in the primary solidification of 625; in turn, a different subsurface phase evolution results from high-temperature oxidation (800°C - 950°C). To evaluate the effect of the subsurface microstructure on the fatigue crack initiation stage, high cycle fatigue tests at room temperature in lab air were performed on wrought and LAM-processed 625 samples subjected to no or one of to two pre-oxidation times. Detailed mesostructural, microstructural, and fractographic characterizations were performed before and after the fatigue testing.
9:30 AM Invited
High Temperature Oxidation of Additively Manufactured FeCrAl and Ni-based Alloys: Mohammad Sattari1; Irina Fedorova1; Alberto Visibile1; Kerem Gündüz1; Jan Froitzheim1; Krystyna Stiller1; Mats Halvarsson1; 1Chalmers University of Technology
Additive manufacturing of metallic components has gained considerable attention among researchers in the last few years. A lot of research has been focused on optimizing both the process parameters for different AM techniques and the mechanical properties of AM components. But, so far very little has been published about high temperature degradation of metallic AM materials. In this work we report on high temperature oxidation behaviour of AM FeCrAl and Ni-based alloys. In particular, the influence of microstructure and crystallographic texture on their high temperature oxidation properties is studied in detail by advanced analytical electron microscopy techniques such as STEM/EDX and SEM/EBSD/TKD. The results are compared with materials produced by conventional methods. It will be demonstrated that while the overall oxidation behaviour of AM and conventionally produced FeCrAl alloys is comparable, the unique microstructure and crystallographic texture of the AM material locally influences the oxidation kinetics.
10:00 AM
Microstructural Evolution and Oxidation Behavior of Fe-25Cr-20Ni-1.4Nb-0.2C Steel Fabricated by Laser Powder-bed Fusion: Kinga Unocic1; Marie Romedenne1; Peeyush Nandwana1; Sebastien Dryepondt1; 1Oak Ridge National Laboratory
A high temperature austenitic stainless steel (Fe-25Cr-20Ni-1.4Nb-0.2C) was fabricated by laser powder-bed fusion (LPBF), which produces refine microstructure and can result in local chemical heterogeneities that could affect oxidation behavior. A detail microstructural characterization of as-build steel revealed that random grain boundaries mainly contained large elongated NbC and some Cr-rich carbides. Within the sub-grain cellular structure mainly nanoscale NbC were observed. The steel oxidation behavior was compared at 650ºC and 700º C in air+10%H2O and at 800C in air with the oxidation behavior of similar wrought austenitic steels. The impact of as printed surface finish and evolution of the microstructure on the oxide products will be discussed. This research was sponsored by the U.S. Department of Energy, Energy Efficiency & Renewable Energy, Vehicle Technologies Office, Propulsion Materials Program. Microscopy performed as part of a user project at the Center for Nanophase Materials Sciences (CNMS), which is a U.S. DOE Office of Science User Facility and US DOE, Office of Nuclear Energy, Fuel Cycle R&D Program and the Nuclear Science User Facilities.
10:20 AM Invited
High Temperature Oxidation and Corrosion of LBM and EBM Ni-base Superalloys and Ti Alloys: Daniel Monceau1; Tom Sanviemvongsak2; Antoine Casadebaigt3; Annabelle Vernouillet4; Bruno Macquaire5; Jonathan Hugues6; Sebastien Doublet7; Aurélie Vande Put1; 1CIRIMAT Laboratory; 2CIRIMAT Laboratory; Safran Tech; 3CIRIMAT Laboratory; IRT Saint Exupery; 4CIRIMAT Laboratory; Air Liquide; 5Safran Tech; 6IRT Saint Exupery; 7Air Liquide
Additively Manufactured Alloys have specific features including surface morphology, surface and bulk microstructures, texture, chemical segregations and impurities and fabrication defects. It will be shown, through several cases dealing with alloys in use in the industry (aeronautic and petrochemical), how these parameters can affect or not the isothermal, interganular and cyclic oxidation, hot corrosion and metal dusting. Recent results on 718, 738, 625, HX, TA6V will be exposed.