High-strain-rate superplasticity of an Al-4.4Cu-1.5Mg/21SiCWcomposite sheet

G. Q. Tong, Kang Cheung Chan

Research output: Journal article publicationJournal articleAcademic researchpeer-review

12 Citations (Scopus)

Abstract

High-strain-rate superplasticity (HSRS) of an Al-4.4Cu-1.5Mg/21SiCWcomposite sheet was evaluated by tensile tests and microstructural characterization over a range of initial strain rates from 1.67 x 10-3to 1.67 x 100s-1and temperatures from 723 to 818 K. The strain rate sensitivity exponent of the composite was found to be approximately 0.34 at a strain rate of 10-2-100s-1and at temperatures between 723 and 818 K. From the experimental findings, the strain rate sensitivity exponent is almost constant during deformation. A maximum elongation of ~446% was obtained at 3.33 x 10-1s-1and at 793 K, which is near the partial melting temperature of the composite. The threshold stress is strongly temperature dependent. The cavitation behavior of the composite during deformation was also examined and compared with that of a typical superplastic aluminum alloy (A17475). The experimental results revealed that the cavity growth was essentially plastic-controlled. It was suggested that the presence of liquid phase was beneficial to nucleation at the interfaces and limited the rate of cavitation growth.
Original languageEnglish
Pages (from-to)218-224
Number of pages7
JournalMaterials Science and Engineering A
Volume286
Issue number2
DOIs
Publication statusPublished - 15 Jul 2000

Keywords

  • Aluminum-based composite
  • Cavitation
  • Strain rate sensitivity exponent
  • Superplasticity
  • Threshold stress

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

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