Sie können Bookmarks mittels Listen verwalten, loggen Sie sich dafür bitte in Ihr SLUB Benutzerkonto ein.
Medientyp:
E-Book
Titel:
Quantitative Analysis of the Deformation Modes and Cracking Modes During Low-Cycle Fatigue of a Rolled Az31b Magnesium Alloy
:
The Influence of Texture
Beschreibung:
The anisotropy of mechanical behavior, as extensively reported in wrought Mg alloys, is ultimately associated with the variation of deformation modes. The influences of texture on the slip/twinning-detwinning activity, cracking modes and mechanical behaviors of a hot-rolled AZ31B alloy during strain-controlled low-cycle fatigue were investigated quantitatively and statistically by quasi-in-situ EBSD observations coupled with slip trace analysis. The fundamental difference in the cracking modes and fatigue behaviors between the 0°, 45°, and 90° samples (i.e., under loading directions of the normal direction (ND), 45°, and rolling direction (RD)) is ascribed to the distinct activation sequences of deformation modes. The cyclic deformation-mode transitions throughout the whole fatigue life can be summarized as: (I) the 0° sample: basal slip + tension twinning→detwinning + basal slip; (II) the 45° sample: basal slip→ basal slip; (III) the 90° sample: tension twinning → detwinning + basal slip. The underlying mechanism for the texture-dependency of deformation modes is discussed. Cracking modes are also closely related to the texture. Intergranular cracking was the primary cracking mode for the 0° and 45° samples, while tension twinning (TTW) cracking was the major cracking mode in the 90° sample. The factors governing the site where microcracks are nucleated are analyzed