Additive Manufacturing of Shape Memory Alloys

Webinar 5

SPEAKER I

Christian Leinenbach (Empa-Swiss Federal Laboratories for Materials Science and Technology, Switzerland)

Control of microstructure and shape memory properties of a Fe-Mn-Si-based shape memory alloy during laser powder bed fusion

 

Abstract: This presentation will explore some recent advances in modifying the microstructure of FeMnSi-based shape memory alloys (SMAs) and thereby their shape memory properties through laser powder bed fusion (L-PBF). We demonstrate how varying the scan speed produces samples with coarse elongated grains with strong <001> orientation or with finer equiaxed grains. Furthermore, it is shown how significant microstructural variations are achieved by modifying L-PBF scanning strategies. Selective Mn evaporation is exploited to tailor phase compositions, resulting in graded-microstructure samples with distinct bcc-δ and fcc-γ phases. These approaches enhance the shape memory effect and strength of FeMnSi-based SMAs, offering valuable insights for advancing additive manufacturing technologies for high performance SMA applications.

 

Related publications:

  • I. Ferretto, A. Borzi, D. Kim, N.M. Della Ventura, E. Hosseini, W.J. Lee, C. Leinenbach, Control of microstructure and shape memory properties of a Fe-Mn-Si-based shape memory alloy during laser powder bed fusion, Additive Manufacturing Letters 3 (2022) 100091
  • I. Ferretto, A. Sharma, D. Kim, N.M. Della Ventura, X. Maeder, J. Michler, E. Hosseini, W.J. Lee, C. Leinenbach, Fabrication of FeMnSi-based shape memory alloy components with graded-microstructures by laser powder bed fusion, Additive Manufacturing 78 (2023) 103835

SPEAKER II

Philipp Krooß (University of Kassel, Institute of Materials Engineering – Metallic Materials, Germany)

Electron Beam Powder Bed Fusion of Binary Ni-Ti Shape Memory Alloys – On The Impact of TiC on Functional Properties

 

Abstract: Shape memory alloys (SMA), such as Ni-Ti, gained a lot of attention as promising materials for actuation and damping applications. Whereas thermomechanical processing widened potential applications of these alloys in the last decades, additive manufacturing (AM) processes are still limited. However, the possibility to process near-net shaped functional materials still motivates recent research in the field of AM. Especially the characterization of microstructural and functional properties in correlation with process parameters are in focus. The present study focuses on the impact of an increased carbon content in a Ni-Ti SMA processed via electron beam powder bed fusion. The functional properties of the processed material are discussed in view of chemical and microstructural findings. The results reveal a high reversibility as well as excellent cyclic stability of the superelastic material properties.

 

Related publications:

  • P. Krooß, C. Lauhoff, T. Gustmann, T. Gemming, C. Sobrero, F. Ewald, F. Brenne, T. Arold, M. Nematolahi, M. Elahinia, J. Thielsch, J. Hufenbach, T. Niendorf, “Additive Manufacturing of Binary Ni–Ti Shape Memory Alloys Using Electron Beam Powder Bed Fusion: Functional Reversibility Through Minor Alloy Modification and Carbide Formation,” Shap. Mem. Superelasticity 8, 2022, 452-462. DOI: https://doi.org/10.1007/s40830-022-00400-2