Microstructure and Corrosion Behavior of Functionally Graded Wire Arc Additive Manufactured Steel Combinations

steel research international, vol. 92

Abstract

Functionally graded materials (FGM) have gained many interests for various applications and are designed to match special requirements in local properties (e.g., corrosion behavior), which highly determines the component's lifetime. The corrosion behavior is strongly dependent on the chemical composition and the microstructure of the designed materials. Therefore, two FGM combinations are designed using wire arc additive manufacturing (WAAM) with a linear changing material deposition from G 3Si1 to G 19 9L Si (combination 1) and G 18L Nb to G 19 9L Si (combination 2). The microstructure at different positions is analyzed using optical light microscopy (OLM), scanning electron microscopy with attached energy dispersive X‐ray spectroscopy (SEM/EDS), and X‐ray diffraction (XRD). The electrochemical corrosion behavior in 0.6 m NaCl solution is determined by cyclic potentiodynamic polarization (CPDP) including SEM imaging after CPDP to determine the pit size and morphology. The phase formation sequences of ferrite (α and δ), martensite, and types of austenite are discussed regarding the chemical gradient. The pitting corrosion resistance is enhanced for both combinations in direction to G 19 9L Si due to the increase in Cr and/or Ni, while the pit morphology changes in dependence of the presence of various microstructures.

Authors 6

1. René Daniel Pütz Aachen Division of Materials Science and Engineering Foundry Institute Chair of Corrosion and Corrosion Protection Division of Materials Science and Engineering Foundry Institute Chair of Corrosion and Corrosion Protection

   RWTH Aachen University

   Affiliation as printed

   Division of Materials Science and Engineering Foundry Institute Chair of Corrosion and Corrosion Protection RWTH Aachen University Intzestr. 5 52072 Aachen Germany

   Division of Materials Science and Engineering, Foundry Institute, Chair of Corrosion and Corrosion Protection, RWTH Aachen University, Intzestr. 5, 52072 Aachen, Germany

2. Yudha Pratesa Aachen Division of Materials Science and Engineering Foundry Institute Chair of Corrosion and Corrosion Protection Division of Materials Science and Engineering Foundry Institute Chair of Corrosion and Corrosion Protection

   RWTH Aachen University

   Affiliation as printed

   Division of Materials Science and Engineering Foundry Institute Chair of Corrosion and Corrosion Protection RWTH Aachen University Intzestr. 5 52072 Aachen Germany

   Division of Materials Science and Engineering, Foundry Institute, Chair of Corrosion and Corrosion Protection, RWTH Aachen University, Intzestr. 5, 52072 Aachen, Germany

3. Lukas Oster Aachen Division of Mechanical Engineering Welding and Joining Institute Division of Mechanical Engineering Welding and Joining Institute

   RWTH Aachen University

   Affiliation as printed

   Division of Mechanical Engineering Welding and Joining Institute RWTH Aachen University Pontstr. 49 52062 Aachen Germany

   Division of Mechanical Engineering, Welding and Joining Institute, RWTH Aachen University, Pontstr. 49, 52062 Aachen, Germany

4. Rahul Sharma Aachen Division of Mechanical Engineering Welding and Joining Institute Division of Mechanical Engineering Welding and Joining Institute

   RWTH Aachen University

   Affiliation as printed

   Division of Mechanical Engineering Welding and Joining Institute RWTH Aachen University Pontstr. 49 52062 Aachen Germany

   Division of Mechanical Engineering, Welding and Joining Institute, RWTH Aachen University, Pontstr. 49, 52062 Aachen, Germany

5. Uwe Reisgen Aachen Division of Mechanical Engineering Welding and Joining Institute Division of Mechanical Engineering Welding and Joining Institute

   RWTH Aachen University

   Affiliation as printed

   Division of Mechanical Engineering Welding and Joining Institute RWTH Aachen University Pontstr. 49 52062 Aachen Germany

   Division of Mechanical Engineering, Welding and Joining Institute, RWTH Aachen University, Pontstr. 49, 52062 Aachen, Germany

6. Daniela Zander corresponding Aachen Division of Materials Science and Engineering Foundry Institute Chair of Corrosion and Corrosion Protection Division of Materials Science and Engineering Foundry Institute Chair of Corrosion and Corrosion Protection

   RWTH Aachen University

   Affiliation as printed

   Division of Materials Science and Engineering Foundry Institute Chair of Corrosion and Corrosion Protection RWTH Aachen University Intzestr. 5 52072 Aachen Germany

   Division of Materials Science and Engineering, Foundry Institute, Chair of Corrosion and Corrosion Protection, RWTH Aachen University, Intzestr. 5, 52072 Aachen, Germany