Author:
Maier Andreas,Rühr Manuel,Tangermann-Gerk Katja,Stephan Marcel,Roth Stephan,Schmidt Michael
Abstract
Purpose
Additive manufacturing (AM) of duplex stainless steels (DSS) is still challenging in terms of simultaneously generating structures with high build quality and adequate functional properties. This study aims to investigate comprehensive process-material-property relationships resulting from both laser-directed energy deposition (DED-LB/M) and laser powder bed fusion (PBF-LB/M) of DSS 1.4462 in as-built (AB) and subsequent heat-treated (HT) states.
Design/methodology/approach
Cuboid specimens made of DSS 1.4462 were generated using both AM processes. Porosity and microstructure analyses, magnetic-inductive ferrite and Vickers hardness measurements, tensile and Charpy impacts tests, fracture analysis, critical pitting corrosion temperature measurements and Huey tests were performed on specimens in the AB and HT states.
Findings
Correlations between the microstructural aspects and the resulting functional properties (mechanical properties and corrosion resistance) were demonstrated and compared. The mechanical properties of DED-LB/M specimens in both material conditions fulfilled the alloy specifications of 1.4462. Owing to the low ductility and toughness of PBF-LB/M specimens in the AB state, a post-process heat treatment was required to exceed the minimum alloy specification limits. Furthermore, the homogenization heat treatment significantly improved the corrosion resistance of DED- and PBF-processed 1.4462.
Originality/value
This study fulfills the need to investigate the complex relationships between process characteristics and the resulting material properties of additively manufactured DSS.
Reference37 articles.
1. Effect of sigma phase in wire arc additive manufacturing of super duplex stainless steel;Metals,2021
2. Optimization of laser metal deposition process for 2205 duplex stainless steel;Key Engineering Materials,2022
3. ASTM International (2018), “ASTM G150-13: standard test method for electrochemical critical pitting temperature testing of stainless steels”, West Conshohocken, PA.
4. ASTM International (2021), “ASTM A262-15: standard practices for detecting susceptibility to intergranular attack in austenitic stainless steels”, West Conshohocken, PA.
5. Wire laser metal deposition of 22% Cr duplex stainless steel: as-deposited and heat-treated microstructure and mechanical properties;Journal of Materials Science,2022