On the effects of the Mg content on the critical strain for the jerky flow of Al-Mg alloys

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:631

Article

Ait-Amokhtar, H.¹  Fressengeas, C.²  Bouabdallah, K.³ 

[1] Univ Bejaia, Fac Sci Exactes, Lab Physicochim Mat & Catalyse LPCMC, Bejaia 06000, Algeria

[2] Univ Lorraine, CNRS, LEM3, F-57045 Metz, France

[3] Univ Msila, Fac Technol, Msila 28000, Algeria

关键词: Al-Mg alloys;    Jerky flow;    Dynamic strain aging;    Portevin-Le Chatelier effect;    Critical strain;   

DOI  :  10.1016/j.msea.2015.02.055

来源: Elsevier

【 摘 要 】

The jerky flow of Al-Mg alloys is investigated during tensile tests at imposed strain rate and room temperature. The strain and strain rate dependences of the magnitude of the stress drops, the range of plastic instability and the critical strain for the onset of serrations are studied in connection with the Mg content. In the low strain rate part of the strain rate range of instability, the critical strain decreases with the Mg content. The critical strain rate corresponding to the minimum of the critical strain vs. applied strain rate curve shifts to larger values when the Mg content increases. This behavior leads to an enlargement of the strain rate domain of inverse behavior of the critical strain, at the expense of the domain of normal behavior. In the high strain rate part of the range of instability, the critical strain does not depend on the Mg content. These results are discussed in accordance with dynamic strain aging mechanisms. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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