A 3D frame-bridge sample was produced by wire arc additive manufacturing (WAAM) on a low carbon steel substrate using the Ni 50.9 Ti 49.1 shape memory wire with a diameter of 1.2 mm. The sample consisted of a rectangular frame and three bridges. The structure and chemical composition were studied in different zones: the frame, the bridge or joint of the frame and the bridge using light and scanning electron microscopy with energy dispersive X-ray spectroscopy. It was shown that the structure of the frame and the bridge located far from the joint was close to the “walls” produced by WAAM: a columnar grain grew across the layers and the equiaxed grains appeared on the top of the layer. The structure of the joint between frame and bridge significantly differed from the “walls”: from the frame side, columnar grains were found across and alone the layers, whereas, from the bridge side the columnar gains were observed in the first layer only. The study of the chemical composition showed that the Fe and C elements diffused to the sample from the low carbon steel substrate. As a result, TiC precipitates appeared in all layers that led to the alloy hardening. Fe atoms penetrated to the NiTi phase that suppressed the martensitic transformation.

Translated title of the contributionСтруктура 3D образца типа «рамка-мост» сплава NiTi, наплавленного на низкоуглеродистую подложку методом электродуговой послойной наплавки
Original languageEnglish
Pages (from-to)496-500
Number of pages5
JournalLetters on Materials
Volume10
Issue number4
DOIs
StatePublished - 2020

    Scopus subject areas

  • Condensed Matter Physics
  • Materials Science (miscellaneous)
  • Materials Science(all)

    Research areas

  • additive manufacturing, NiTi shape memory alloys, microstructure, Wire arc additive manufacturing, 3D STRUCTURE, NiTi shape memory alloy, 3D structure, Additive manufacturing, Microstructure

ID: 71871939