Role of initial {10−12} twin in the fatigue behavior of rolled Mg–3Al–1Zn alloy

Received 19 November 2009; received in revised form 12 January 2010; accepted 12 January 2010. published online 15 January 2010.

Initial {10−12} twin influenced the plastic deformation mechanism activated during fatigue deformation, especially during compressive loading, by enhancing the activity of the detwinning mechanism. With the aid of initial {10−12} twin, compressive deformation could be fully accommodated by detwinning alone. This change in the predominant plastic deformation mechanism during compressive loading significantly decreased compressive flow stress, causing an increase in mean stress, and thus deteriorated the fatigue resistance of the material.

Keywords: Magnesium alloy, Low-cycle fatigue, {1

−1

2} twinning–detwinning, Initial {1

−1

2} twin, Mean stress

a Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea

b Division of Industrial Metrology, Korea Research Institute of Standards and Science, Daejeon 305-340, Republic of Korea

Corresponding authors. Tel.: +82 42 868 5868; fax: +82 42 868 5032 (S.-G.H); tel.: +82 54 279 2141; fax: +82 54 279 2399 (C.S.L.).

PII: S1359-6462(10)00022-9

doi:10.1016/j.scriptamat.2010.01.021

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