Investigation of tension-compression asymmetry of magnesium by use of the acoustic emission technique
2011
Abstract
The acoustic emission (AE) technique has been applied to in situ investigations of deformation processes of polycrystalline magnesium with various grain sizes in tension and compression from 20 to 300 degrees C. The AE signal of twin nucleation exhibited an asymmetry corresponding to the tension-compression flow stress asymmetry due to easier {10 (1) over bar2} twinning in compression.
A maximum in the AE signal is observed at 200 degrees C and is interpreted as a consequence of the synergetic effect of twinning and greater slip activity at higher temperatures. A larger grain size (600 mu m) facilitated twinning. (C) 2011 Elsevier B.V.
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