Co-Deformation of the Metallic Matrix and Intermetallic Phases in an Mg-3.68Al-3.8Ca Alloy

Determination of the Rate Dependence of Damage Formation in Metallic‐Intermetallic Mg–Al–Ca Composites at Elevated Temperature using Panoramic Image Analysis

“…The deformation mechanisms of the Mg-C36 Laves phase observed under these and similar conditions have been reported elsewhere. [8,29,52] Examples of the formation of extension twins in the α-Mg phase are given in Figure 6. The three variants of extension twins within one α-Mg grain are highlighted in Figure 6a.…”

“…[1][2][3] In contrast, the presence of intermetallics naturally leads to decreased tensile elongation, as the present intermetallic phases such as Mg 17 Al 12 or Laves phases such as CaAl 2 (C15), Ca(Mg,Al) 2 (C36), and CaMg 2 (C14) are hard and brittle, particularly below approximately two-thirds of their melting temperature. [4][5][6][7][8][9][10][11] As both low and elevated temperature regimes, that is room temperature and temperatures around and above 150 °C, are of interest in application, the underlying deformation and damage mechanisms and their thermal activation need to be understood. In particular, the competition between brittle fracture and plasticity, enabled by dislocation glide or diffusional processes, may be expected to determine any temperaturedependent macroscopic transitions in mechanical behavior.…”

“…[27] In Mg-Al-Ca alloys, the Mg and Laves phases have substantially different mechanical properties, resulting in heterogeneous deformation. [8,28,29] Under tensile loading or during indentation, cracks form in the Laves phase or at α-Mg/Laves phase interfaces. [3,8,21,28,30,31] In addition to cracking, plastic deformation has also been observed in the Laves phases surrounded by α-Mg matrix.…”

“…[8,28,29] Under tensile loading or during indentation, cracks form in the Laves phase or at α-Mg/Laves phase interfaces. [3,8,21,28,30,31] In addition to cracking, plastic deformation has also been observed in the Laves phases surrounded by α-Mg matrix. [8,16,29,32] The codeformation behavior of α-Mg and Laves phases can be affected substantially by the strain rate, in addition to other factors like orientation relationships and temperature of deformation.…”

“…[3,8,21,28,30,31] In addition to cracking, plastic deformation has also been observed in the Laves phases surrounded by α-Mg matrix. [8,16,29,32] The codeformation behavior of α-Mg and Laves phases can be affected substantially by the strain rate, in addition to other factors like orientation relationships and temperature of deformation. [29] Strain rate and temperature are known to affect the deformation and fracture behavior of materials considerably.…”