An extruded AZ31B (Mg-3Al-1Zn-0.5Mn) magnesium alloy with a twin volume fraction of 60% was subjected to fully reversed strain-controlled tension-compression along the extrusion direction at strain amplitudes ranging from 0.23% to 0.45%. Dislocation slips were the dominant plastic deformation mechanisms without involving persistent twinning-detwinning. At an identical strain amplitude, the fatigue life of the pre-twinned alloy was much lower than that of the as-extruded alloy. Fatigue cracks were mainly initiated on the prismatic or prismatic-basal slip bands in the parent grains. The material volume reduction of the parent grains in the pre-twinned alloy enhanced fatigue damage. Twin cracks were not observed.
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Effect of initial texture on fatigue properties of extruded ZK60 magnesium alloy
The effect of initial texture on cyclic deformation behavior of extruded ZK60 magnesium (Mg) alloy was experimentally investigated under strain‐controlled loading with the strain amplitudes at 4%, 1%, and 0.35%. The testing specimens were taken from extrusion direction (ED), transverse direction (TD), and a material precompressed to 9.4% along the ED (ED−9.4%). At a high strain amplitude of 4%, the cyclic deformation modes of ED and ED−9.4%specimens are similar, and they experience twinning exhaustion →
- NSF-PAR ID:
- 10053445
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Fatigue & Fracture of Engineering Materials & Structures
- Volume:
- 41
- Issue:
- 7
- ISSN:
- 8756-758X
- Page Range / eLocation ID:
- p. 1504-1513
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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