Crack Paths 2012

cracks is demonstrated. Also the general preferential growth direction and formation of

“optically dark area” (ODA)can be linked to adjacent grain orientations and sub-grain

structures such as martensitic laths. A connection between the formation of O D Aand

local martensitic lath bundles in the microstructure surrounding a non-metallic inclusion

could provide a partial explanation to the formation and origin of the ODA.

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