The role played by deformation twin boundaries in the brittle crack propagation and fracture resistance of poly and single crystals of Fe–3wt%Si steel was considered. Three-point bend, impact and miniaturized disc tests were undertaken at 77 to 273K. The fractographic features were characterized with attention being given to (i) the role of the {112} deformation twins on the propagation of the {001} cleavage cracks and (ii) the process-zone of the propagating cleavage cracks. The results were discussed with reference to three-dimensional model predictions.

The Role of Deformation Twins in Brittle Crack Propagation in Iron–Silicon Steel. F.Sorbello, P.E.J.Flewitt, G.Smith, A.G.Crocker: Acta Materialia, 2009, 57[9], 2646-56