Microstructure Based Study on the Low Cycle Fatigue Behavior of Stainless Steel 316L manufactured by Laser Powder Bed Fusion
- Due to the advantages of Laser Powder Bed Fusion (PBF-LB), i.e., design freedom and the possibility to manufacture parts with filigree structures, and the considerable amount of knowledge available for 316L in its conventional variant, the mechanical behavior, and related microstructure-property relationships of PBF-LB/316L are increasingly subject of research. However, many aspects regarding the - application-relevant - mechanical behavior at high temperatures are not yet fully understood. Here, we present the results of an experimental study on the LCF behavior of PBF-LB/316L featuring a low defect population, which makes this study more microstructure-focused than most of the studies in the literature. The LCF tests were performed between room temperature (RT) and 600 °C. The mechanical response is characterized by strain-life curves, and hysteresis and cyclic deformation curves. The damage and deformation mechanisms are studied with X-ray computed tomography, and optical andDue to the advantages of Laser Powder Bed Fusion (PBF-LB), i.e., design freedom and the possibility to manufacture parts with filigree structures, and the considerable amount of knowledge available for 316L in its conventional variant, the mechanical behavior, and related microstructure-property relationships of PBF-LB/316L are increasingly subject of research. However, many aspects regarding the - application-relevant - mechanical behavior at high temperatures are not yet fully understood. Here, we present the results of an experimental study on the LCF behavior of PBF-LB/316L featuring a low defect population, which makes this study more microstructure-focused than most of the studies in the literature. The LCF tests were performed between room temperature (RT) and 600 °C. The mechanical response is characterized by strain-life curves, and hysteresis and cyclic deformation curves. The damage and deformation mechanisms are studied with X-ray computed tomography, and optical and electron microscopy. The PBF-LB/M/316L was heat treated at 450 °C for 4 h, and a hot‑rolled (HR) 316L variant with a fully recrystallized equiaxed microstructure was tested as a reference. Besides, selected investigations were performed after a subsequent heat treatment at 900 °C for 1 h. The PBF-LB/316L exhibits higher cyclic stresses than HR/316L for most of the fatigue life, especially at room temperature. At the smallest strain amplitudes, the fatigue lives of PBF-LB/M/316L are markedly shorter than in HR/316L. The main damage mechanisms are multiple cracking at slip bands (RT) and intergranular cracking (600 °C). Neither the melt pool boundaries nor the gas porosity have a significant influence on the LCF damage mechanism. The cyclic stress-strain deformation behavior of PBF-LB/M/316L features an initial hardening followed by a continuous softening. The additional heat treatment at 900 °C for 1 h led to decreased cyclic stresses, and a longer fatigue life.…
Autor*innen: | Luis Alexander Ávila CalderónORCiD |
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Koautor*innen: | Birgit Rehmer, Tiago Werner, Alexander Ulbricht, Gunther MohrORCiD, Birgit Skrotzki, Alexander Evans |
Dokumenttyp: | Vortrag |
Veröffentlichungsform: | Präsentation |
Sprache: | Englisch |
Jahr der Erstveröffentlichung: | 2024 |
Organisationseinheit der BAM: | 5 Werkstofftechnik |
5 Werkstofftechnik / 5.2 Metallische Hochtemperaturwerkstoffe | |
8 Zerstörungsfreie Prüfung | |
8 Zerstörungsfreie Prüfung / 8.5 Röntgenbildgebung | |
9 Komponentensicherheit | |
9 Komponentensicherheit / 9.4 Integrität von Schweißverbindungen | |
9 Komponentensicherheit / 9.6 Additive Fertigung metallischer Komponenten | |
DDC-Klassifikation: | Technik, Medizin, angewandte Wissenschaften / Ingenieurwissenschaften / Ingenieurwissenschaften und zugeordnete Tätigkeiten |
Freie Schlagwörter: | 316L; AGIL; Heat Treatment; Laser Poeder Bed Fusion; Low Cycle Fatigue; Microstructure |
Themenfelder/Aktivitätsfelder der BAM: | Material |
Material / Additive Fertigung | |
Veranstaltung: | 4th Symposium on Materials and Additive Manufacturing |
Veranstaltungsort: | Berlin, Germany |
Beginndatum der Veranstaltung: | 12.06.2024 |
Enddatum der Veranstaltung: | 14.06.2024 |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 01.07.2024 |
Referierte Publikation: | Nein |
Eingeladener Vortrag: | Nein |