Low-strain plasticity in a high pressure die cast Mg-Al alloy

作者：Yang K Vanna^*; Caceres C H; Nagasekhar A V; Easton M A

来源：Modelling and Simulation in Materials Science and Engineering, 2012, 20(2): 024010.

DOI：10.1088/0965-0393/20/2/024010

The Kocks-Mecking method was used to compare the strain-hardening behavior at low strains of high pressure die cast Mg-9 mass% Al alloy and gravity cast fine grained pure Mg specimens. The alloy specimens exhibited a rounded flow curve in contrast with the pure metal%26apos;s for which macroscopic yielding occurred at a well-defined stress. Microhardness mapping of the cross-section of an alloy specimen showed a surface layer, or skin, with hardness values similar to 20 HV above those of the centre or core region. On the assumption that the core strain hardens at the same rate as the pure Mg specimen, it was estimated that similar to 20% of the alloy specimen%26apos;s cross-section was still elastic when the core reached full plasticity. The micromechanics of the elasto-plastic transition in the alloy specimens are discussed.

• 出版日期2012-3-1
• 单位中国空间技术研究院