Computational Investigation of Hardness Evolution During Friction-Stir Welding of AA5083 and AA2139 Aluminum Alloys

Abstract

A fully coupled thermo-mechanical finite-element analysis of the friction-stir welding (FSW) process developed in our previous work is combined with the basic physical metallurgy of two wrought aluminum alloys to predict/assess their FSW behaviors. The two alloys selected are AA5083 (a solid-solution strengthened and strain-hardened/stabilized Al-Mg-Mn alloy) and AA2139 (a precipitation hardened quaternary Al-Cu-Mg-Ag alloy). Both of these alloys are currently being used in military-vehicle hull structural and armor systems. In the case of non-age-hardenable AA5083, the dominant microstructure- evolution processes taking place during FSW are extensive plastic deformation and dynamic re-crystallization of highly deformed material subjected to elevated temperatures approaching the melting temperature. In the case of AA2139, in addition to plastic deformation and dynamic recrystallization, precipitates coarsening, over-aging, dissolution, and re-precipitation had to be also considered. Limited data available in the open literature pertaining to the kinetics of the aforementioned microstructure evolution processes are used to predict variation in the material hardness throughout the various FSW zones of the two alloys. The computed results are found to be in reasonably good agreement with their experimental counterparts.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2011
Accession Number
ADA580118

Entities

People

  • Bryan A. Cheeseman
  • Chianfong Yen
  • G. Arakere
  • M. Grujičić

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Space

DTIC Thesaurus Topics

  • Aluminum
  • Aluminum Alloys
  • Crystal Structure
  • Dispersion Hardening
  • Engineering
  • Friction Stir Welding
  • Grain Boundaries
  • Grain Size
  • Hardening
  • Hardness
  • Materials
  • Materials Engineering
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Physical Metallurgy
  • Solid Solutions

Fields of Study

  • Materials science

Readers

  • Computational Fluid Dynamics (CFD)
  • Manufacturing Engineering.
  • Powder metallurgy of Titanium alloys.