Microstructure of laser melted Zn-Al-based alloy

Y. H. Zhu, Hau Chung Man, Wing Bun Lee

Research output: Journal article publicationJournal articleAcademic researchpeer-review

7 Citations (Scopus)

Abstract

The microstructure of a laser treated eutectoid Zn-Al-based alloy (Zn-22% Al-2% Cu, in wt.%) has been investigated using X-ray diffraction (XRD), back-scattered scanning electron microscopy (BSEM) techniques. The alloy specimen was previously furnace cooled, then treated by continuous laser scanning. Various microstructures were observed in the laser treated alloy specimen. The molten zone is composed mainly of a fine dendritic structure of zinc-rich βs′-phase. In the intermediate region between the molten zone and the bulk part of the specimen, a typical dendritic structure of cast eutectoid alloy is formed, i.e. an aluminum-rich αs′-phase as the core of the dendrites, surrounded by βs′-phase. Zinc-rich η- and ε-phases form in the inter-dendritic region. These were distinct from the lamellar structure in the bulk part of the specimen. The effect of laser scan speed on the microstructure and phase transformation of various metastable phases in the alloy is also discussed.
Original languageEnglish
Pages (from-to)296-301
Number of pages6
JournalJournal of Materials Processing Technology
Volume139
Issue number1-3 SPEC
DOIs
Publication statusPublished - 20 Aug 2003

Keywords

  • Cooling rate
  • Laser melting
  • Microstructure
  • Phase transformation
  • Solidification
  • Zn-Al alloy

ASJC Scopus subject areas

  • Materials Science(all)

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