Characterizations of micro-nano structure and tensile properties of a Sc modified Al[sbnd]Mn alloy fabricated by selective laser melting

Jinglin Lu, Xin Lin, Nan Kang, Weidong Huang

Research output: Contribution to journalArticlepeer-review

20 Scopus citations

Abstract

In this work, bulk deposits of a Sc modified Al-Mn-Fe-Si alloy were prepared by selective laser melting (SLM), and the microstructural characteristics and tensile properties of the deposits were analyzed. The as-deposited sample presented a multiscale microstructure consisting of epitaxial columnar grains with width of 30–140 μm, in which there exist α-Al dendrite arrays with average primary dendrite arm spacing of 0.34 μm, and interdendritic nanoscale α-Al + Al6(Mn,Fe) divorced eutectic. After an aging treatment, Al6(Mn,Fe) transformed into Al12(Mn,Fe)3Si, and its morphology gradually evolved from skeleton into particle. Meanwhile, needle-like AlMnSi precipitated and grew up in the α-Al dendrite trunk. The ultimate tensile strength increased from 349 ± 9 MPa in the as-deposited state to 430 ± 3 MPa after aging at 300 °C. However, it dropped to 358 ± 1 MPa when the aging temperature increased to 350 °C. The addition of Sc caused precipitation strengthening of secondary Al3Sc after aging treatment, but the grain refinement effect of primary Al3Sc was inhibited since Sc tended to segregate at the frontier of the Mn-containing pre-precipitates.

Original languageEnglish
Article number111305
JournalMaterials Characterization
Volume178
DOIs
StatePublished - Aug 2021

Keywords

  • Aging treatment
  • Al-Mn alloy
  • Microstructure
  • Selective laser melting
  • Tensile properties

Fingerprint

Dive into the research topics of 'Characterizations of micro-nano structure and tensile properties of a Sc modified Al[sbnd]Mn alloy fabricated by selective laser melting'. Together they form a unique fingerprint.

Cite this