Relationship between position on line X shown in Fig. Relationship between shear displacement d obtained by measuring movement of etch pits along line X shown in Fig.
Conversely, slip lines were clearly observed in Fig. Schematic illustrations of a pure shear test specimen and b finite element model created on the basis of a half shape of the pure shear test specimen. As such, CRSS for slip systems is unable to be determined using the shear stress obtained in the present test. While prismatic slip can be confirmed not to activate at the shear stress of 40 MPa, this was unable to evaluate CRSS. Pure shear tests of Mg single crystals were carried out to evaluate CRSSs for basal and prismatic slips.
The main results are summarized as follows:. Already have an account? Login in here. Journal home Advance online publication Journal issue Featured articles About the journal. Keywords: magnesium single crystal , basal slip , prismatic slip , twin , CRSS critical resolved shear stresses.
Experimental Procedures. Results and Discussion. Table 1 Specimen sizes of pure shear test specimens used in this study. Supplementary materials. Dislocation climb is an alternative mechanism of dislocation motion that allows an edge dislocation to move out of its slip plane.
This atom shift moves the vacancy in line with the half plane of atoms, causing a shift, or positive climb, of the dislocation. An edge dislocation therefore moves in the direction of the Burgers vector, whereas a screw dislocation moves in a direction perpendicular to the Burgers vector. Point defects are lattice defects of zero dimensionality, i.
Typical point defects are impurity atoms in a pure metal, vacancies and self-interstitials. Line defects can be described by gauge theories. Dislocations are linear defects, around which the atoms of the crystal lattice are misaligned. There are two basic types of dislocations, the edge dislocation and the screw dislocation.
The compounds in which the number of positive and negative ions are exactly in the ratios indicated by their chemical formulae are called stoichiometric compounds.
The defects do not disturb the stoichiometry the ratio of numbers of positive and negative ions are called stoichiometric defects. In Schottky defect the difference in size between cation and anion is small. Frenkel defect contains ionic crystals where the anion is larger than the cation. Usually the smaller ion cation leaves its original lattice structure. Atoms permanently leave the crystal.
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