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Electronics and FluidicsFiber Optics and Integrated Optics

Textures in Aluminum and Titanium: Their On-Line Evaluation and Quantitative Effects on Formability

Authors: Chi-Sing Man; KENTUCKY UNIV RESEARCH FOUNDATION LEXINGTON
Abstract:
The main findings of this project were as follows: (1) For samples of an AA5xxx aluminum alloy sheet at temperatures up to 750 deg F, the degree of recrystallization could be monitored by using either resonance-EMAT spectroscopy or laser-ultrasound resonance spectroscopy. (2) Formulae showing explicitly the effects of crystallographic texture on the planar plastic anisotropy of sheets of cubic (e.g., aluminum) and of hexagonal (e.g., titanium) metals in uniaxial tension tests were derived. (3) A constitutive relation pertaining to acousto- elasticity was formulated for prestressed, orthorhombic aggregates of cubic crystallites. (4) For vertically-heterogeneous, prestressed orthorhombic media where the principal stress directions agree with the axes of orthorhombic material symmetry, a high-frequency asymptotic formula was derived which relate the depth variations of stress and texture to the dispersion of surface acoustic waves propagating in a symmetry direction.

Limitations: APPROVED FOR PUBLIC RELEASE
Description: Final rept. 15 May 1998-15 May 2002
Pages: 12
Report Date: 10 AUG 2002
Contract Number: F49620-98-1-0469
Report Number: A623604
Keywords relating to this report:
ALUMINUM
ANISOTROPY
AXES
CRYSTALLOGRAPHY
DEPTH
METALS
NONDESTRUCTIVE TESTING
ONLINE SYSTEMS
ORIENTATION(DIRECTION)
PLANAR STRUCTURES
PLASTICS
RECRYSTALLIZATION
SHEET METAL
STRESSES
SURFACE ACOUSTIC WAVES
SYMMETRY
TENSION
TEST AND EVALUATION
TEXTURE
TITANIUM
UNIDIRECTIONAL
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