Influence of the processing route on the mechanical properties at high temperatures of Mg-Ni-Y-RE alloys containing LPSO-phases

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

卷:673

Article

Gonzalez, S.¹  Perez, P.²  Garces, G.²  Adeva, P.² 

[1] Northumbria Univ, Fac Engn & Environm, Newcastle Upon Tyne NE1 8ST, Tyne & Wear, England

[2] Ctr Nacl Invest Met CENIM CSIC, Dept Met Fis, Avda Gregorio del Amo 8, Madrid 28040, Spain

关键词: Mechanical characterisation;    Magnesium alloys;    LPSO-phase;    Processing route;    Deformation mechanisms;   

DOI  :  10.1016/j.msea.2016.07.077

来源: Elsevier

【 摘 要 】

The mechanical properties at high temperatures of two Mg-Ni-Y-RE alloys prepared by conventional or powder metallurgy routes have been evaluated. All alloys exhibit high-strength up to 250 degrees C but their strength depends more on the composition of the alloy rather than on the processing route. High strength of the alloys arises from their fine grain size but there is an additional contribution of load transfer from the magnesium matrix towards the second phases in the alloys processed by the conventional route while additional hardening in the alloys prepared by powder metallurgy is due to Or-owan mechanism. Above 250 degrees C, the strength drops to very low values but all alloys exhibit high elongations and grain boundary sliding is the controlling mechanism. Grain boundary sliding also induces cracking of the coarse second phases into smaller pieces during the initial stages of plastic deformation of conventionally processed alloys. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

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