Cyclic-tension fatigue of aluminum alloy Al-4Cu-1Mg has been determined by usage of vertically-polarized shear wave (SV) reflection and horizontally-polarized shear wave (SH) transmission methods. Internal friction measured by SV method begins to increase rapidly from normalized fatigue ratio of about 0.5, showing dominating interaction of movable dislocations with the waves, as viscoelastic effect. Propagation time and logarithmic damping ratio in the SH method decrease with an increase of the fatigue degree, due to a shift of residual stress as the acoustoelastic effect. The logarithmic damping ratio shows better correlation with the residual-stress shift than the propagation time because acoustic velocity is considered to be significantly affected by pile-up dislocation.
|Number of pages||8|
|Journal||Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science|
|Publication status||Published - 2009 Jan 9|
ASJC Scopus subject areas
- Condensed Matter Physics
- Mechanics of Materials
- Metals and Alloys