Study of basal < a > and pyramidal < c + a > slips in Mg-Y alloys using micro-pillar compression

Deformation mechanisms of Mg-Ca-Zn alloys studied by means of micropillar compression tests

“…The curves show gradual yielding of the micropillar with the applied strain, that is followed by a region where deformation progresses at constant stress. Large strain bursts are observed in this plateau region and this behavior is similar to that observed in Mg, Mg-Al, Mg-Zn and Mg-Y micropillars deformed in equivalent orientations [24,33,36,42]. The yield stress (to determine the initial CRSS for plastic deformation) was taken from the critical points (denoted by black stars in Fig.…”

“…Sandlöbes et al [23] indicated that the improved ductility of Mg-Y alloys was related to the activation of <c+a> pyramidal dislocations. Curtin et al [10] reported that soluteaccelerated cross-slip contributed to the ductility Mg-Y alloys, and this prediction was confirmed by transmission electron microscopy (TEM) observations [24].…”

“…These experimental results were carried out in polycrystalline samples and it was difficult to determine the actual values of the CRSS for each slip system and twinning because of the influence of different contributions (texture, grain size, cross-slip) to the overall mechanical response. However, novel micromechanical testing techniques have been recently used to assess the fundamental deformation mechanisms of single crystals of Mg [24,[33][34][35][36][37][38][39][40][41][42], Ti [43,44], Al [45,46], and Ta [47] alloys as well as of intermetallic compounds [48,49]. In particular, micropillar compression tests have been used to measure the CRSS for different slip systems as well as CRSS for twin nucleation and growth in pure Mg [33][34][35][36][37] and different Mg alloys [24,[38][39][40][41][42] at ambient and elevated temperature as a function of the solute or precipitate content.…”

“…However, novel micromechanical testing techniques have been recently used to assess the fundamental deformation mechanisms of single crystals of Mg [24,[33][34][35][36][37][38][39][40][41][42], Ti [43,44], Al [45,46], and Ta [47] alloys as well as of intermetallic compounds [48,49]. In particular, micropillar compression tests have been used to measure the CRSS for different slip systems as well as CRSS for twin nucleation and growth in pure Mg [33][34][35][36][37] and different Mg alloys [24,[38][39][40][41][42] at ambient and elevated temperature as a function of the solute or precipitate content. This methodology is applied in this investigation to elucidate the intrinsic effect of solid solution atoms on the deformation mechanisms of Mg-Ca-Zn alloys.…”

Study on the Fine Grain Size and Microhardness at the Interface of AZ31/Mg‐Y Composites

“…[ 7,8 ] The room temperature ductility of Mg–Y alloys was obviously improved compared with pure Mg. [ 9 ] It was observed that the activation of nonbasal slip (e.g., pyramidal ⟨ c + a ⟩ slip) was much enhanced with the addition of Y, which may enable the material to accommodate a higher total strain through the higher number of available independent slip systems. Reduced difference in critical resolved shear stress (CRSS) between slip systems [ 10,11 ] and deceased stacking fault energy [ 12 ] may be responsible for the higher activity of the ⟨ c + a ⟩ dislocation slip in Mg–Y alloys. In addition, with the addition of RE elements, the basal texture was strongly weakened, which enabled the Mg alloys to accommodate more strain along the thickness of sheets through the activation of more basal slip, thus improving the formability.…”