Effect of Thermal Treatment on Corrosion Behavior of AISI 316L Stainless Steel Manufactured by Laser Powder Bed Fusion
Francesco Andreatta,
Alex Lanzutti,
Reynier I. Revilla,
Emanuele Vaglio,
Giovanni Totis,
Marco Sortino,
Iris de Graeve,
Lorenzo Fedrizzi
Affiliations
Francesco Andreatta
Polytechnic Department of Engineering and Architecture, University of Udine, via del Cotonificio 108, 33100 Udine, Italy
Alex Lanzutti
Polytechnic Department of Engineering and Architecture, University of Udine, via del Cotonificio 108, 33100 Udine, Italy
Reynier I. Revilla
Department of Materials and Chemistry, Vrije Universiteit Brussel (VUB), Electrochemical and Surface Engineering (SURF), Pleinlaan 2, 1050 Brussels, Belgium
Emanuele Vaglio
Polytechnic Department of Engineering and Architecture, University of Udine, via del Cotonificio 108, 33100 Udine, Italy
Giovanni Totis
Polytechnic Department of Engineering and Architecture, University of Udine, via del Cotonificio 108, 33100 Udine, Italy
Marco Sortino
Polytechnic Department of Engineering and Architecture, University of Udine, via del Cotonificio 108, 33100 Udine, Italy
Iris de Graeve
Department of Materials and Chemistry, Vrije Universiteit Brussel (VUB), Electrochemical and Surface Engineering (SURF), Pleinlaan 2, 1050 Brussels, Belgium
Lorenzo Fedrizzi
Polytechnic Department of Engineering and Architecture, University of Udine, via del Cotonificio 108, 33100 Udine, Italy
The effect of post-processing heat treatment on the corrosion behavior of AISI 316L stainless steel manufactured by laser powder bed fusion (L-PBF) is investigated in this work. Produced stainless steel was heat treated in a broad temperature range (from 200 °C to 1100 °C) in order to evaluate the electrochemical behavior and morphology of corrosion. The electrochemical behavior was investigated by potentiodynamic and galvanostatic polarization in a neutral and acidic (pH 1.8) 3.5% NaCl solution. The microstructure modification after heat treatment and the morphology of attack of corroded samples were evaluated by optical and scanning electron microscopy. The fine cellular/columnar microstructure typically observed for additive-manufactured stainless steel evolves into a fine equiaxed austenitic structure after thermal treatment at high temperatures (above 800 °C). The post-processing thermal treatment does not negatively affect the electrochemical behavior of additive-manufactured stainless steel even after prolonged heat treatment at 1100 °C for 8 h and 24 h. This indicates that the excellent barrier properties of the native oxide film are retained after heat treatment.
