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Accession Number ADA562397
Title Spatial Mechanical Response and Strain Gradient Evolution of Friction Stir Welded Aluminum-2139.
Publication Date Feb 2012
Media Count 30p
Personal Author B. Justusson C. Fountzoulas C. Yen J. Medintz J. Yu
Abstract With current involvements of the U.S. Military in various peace- keeping and combat operations throughout the world, there is an increase in the deployment of armored military vehicles. Traditional armoring techniques have performed well against particular threats, but, in the recent combat operations, a new threat of improvised explosive devices, the vulnerability of the undercarriage, is being exposed. While thick, steel-structural members have been used in the past, an effort to make them more agile and deployable has caused a push toward lightweight materials. Advanced aluminum alloys, such as AA-2139, are attractive candidates because of their high strength and lower density than steel. Single-body construction can eliminate joint failure but requires a new joining technique. Friction stir welding (FSW) is a solid-state joining technique that combines extreme plastic deformation coupled with localized heat flux to create unique microstructure joints. In general, the mechanical properties are dependent on the formation of the microstructure. To the best of our knowledge, these microstructural zones and the quality of the weld have not fully been characterized under blast loading. Finite-element simulations have been used to predict the mechanical response of blast loading, but the effects of the microstructural zones on blast loading are not fully understood. In the present work, the spatial mechanical response of a FSW joint is analyzed to determine the spatial mechanical properties.
Keywords Aluminum alloys
Finite element method
Friction stir welding (FSW)
Friction welding
Heat flux
Joints
Mechanical properties
Microstructure
Solid state
Strain(Mechanics)
Vulnerability


 
Source Agency Non Paid ADAS
NTIS Subject Category 71N - Nonferrous Metals & Alloys
Corporate Author Oak Ridge Inst. for Science and Education, TN.
Document Type Technical report
Title Note Final rept. Jul 2007-Aug 2011.
NTIS Issue Number 1225
Contract Number ORISE 1120-1120-99

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