An energy analysis of the grain boundary behavior in cleavage cracking in Fe–3wt.%Si alloy
نویسندگان
چکیده
The resistance of high-angle grain boundaries to cleavage cracking in Fe–3wt.%Si bicrystals is discussed in context of linear elastic fracture mechanics based on an energy method. The grain boundary toughness is determined by the fracture work associated with the plastic shear along the grain boundary and the crack-trapping effect. The influence of the crystallographic misorientation and the size effect are analyzed. It is concluded that the toughening effect of the grain boundary is dominated by the tilt and twist angles and is more pronounced for shorter cracks. The numerical results fit with the experimental data quite well. D 2004 Elsevier B.V. All rights reserved.
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