TY - JOUR

T1 - On the Microstructural and Cyclic Mechanical Properties of Pure Iron Processed by Electron Beam Melting

AU - Torrent, Christof Johannes Jaime

AU - Wackenrohr, Steffen

AU - Richter, Julia

AU - Sobrero, César Ernesto

AU - Degener, Sebastian

AU - Krooß, Philipp

AU - Maier, Hans Jürgen

AU - Niendorf, Thomas

N1 - Funding Information: This work was supported by the Deutsche Forschungsgemeinschaft (DFG) under grant number 413259151. The authors acknowledge access to DESY (Hamburg, Germany), a member of the Helmholtz Association HGF. Parts of this research were conducted at PETRA III. The authors gratefully acknowledge experimental support by N. Schell and A. Stark at P07 EH1. Open access funding enabled and organized by Projekt DEAL.

PY - 2021/6/24

Y1 - 2021/6/24

N2 - Additive manufacturing (AM) processes such as electron beam melting (EBM) are characterized by unprecedented design freedom. Topology optimization and design of the microstructure of metallic materials are enabled by rapid progress in this field. The latter is of highest importance as many applications demand appropriate mechanical as well as functional material properties. For instance, biodegradable implants have to meet mechanical properties of human bone and at the same time guarantee adequate cytocompatibility and degradation rate. In this field, pure iron has come into focus in recent studies due to its low toxicity. Hierarchical microstructures resulting from the EBM solidification processes and intrinsic heat treatment, respectively, allow for an adjustment of the degradation behavior and may promote enhanced fatigue strength. Herein, commercially pure iron (cp-Fe) is processed by EBM. Microstructural analysis as well as an evaluation of the cyclic mechanical material properties are conducted. The results are compared to a hot-rolled (HR) reference material. A contradiction observed as the EBM-processed cp-Fe (EBM Fe) shows lower ultimate tensile strength under monotonic loading but improved fatigue properties compared to the HR Fe. It is revealed that such a unique behavior originates from prevailing microstructural features in the EBM as-built condition.

AB - Additive manufacturing (AM) processes such as electron beam melting (EBM) are characterized by unprecedented design freedom. Topology optimization and design of the microstructure of metallic materials are enabled by rapid progress in this field. The latter is of highest importance as many applications demand appropriate mechanical as well as functional material properties. For instance, biodegradable implants have to meet mechanical properties of human bone and at the same time guarantee adequate cytocompatibility and degradation rate. In this field, pure iron has come into focus in recent studies due to its low toxicity. Hierarchical microstructures resulting from the EBM solidification processes and intrinsic heat treatment, respectively, allow for an adjustment of the degradation behavior and may promote enhanced fatigue strength. Herein, commercially pure iron (cp-Fe) is processed by EBM. Microstructural analysis as well as an evaluation of the cyclic mechanical material properties are conducted. The results are compared to a hot-rolled (HR) reference material. A contradiction observed as the EBM-processed cp-Fe (EBM Fe) shows lower ultimate tensile strength under monotonic loading but improved fatigue properties compared to the HR Fe. It is revealed that such a unique behavior originates from prevailing microstructural features in the EBM as-built condition.

KW - additive manufacturing

KW - fatigue

KW - microstructure

KW - pure iron

KW - rotating bending

UR - http://www.scopus.com/inward/record.url?scp=85102272633&partnerID=8YFLogxK

U2 - 10.1002/adem.202100018

DO - 10.1002/adem.202100018

M3 - Article

AN - SCOPUS:85102272633

VL - 23

JO - Advanced engineering materials

JF - Advanced engineering materials

SN - 1438-1656

IS - 6

M1 - 2100018

ER -