physica status solidi (b) · 1968 · 63 citations · 23 references
EngineeringSevere Plastic DeformationSlip BandsMo Single CrystalsMicrostructure-strength RelationshipCrystal FormationAbstract Single CrystalsMaterials ScienceStrain LocalizationCrystal MaterialSolid MechanicsPlasticityMechanical DeformationCrystallographyMicrostructureMaterial AnalysisDislocation InteractionMechanical PropertiesSurface ScienceApplied PhysicsCondensed Matter PhysicsSlip SystemsMechanics Of MaterialsStereographic Triangle
Abstract Single crystals of molybdenum, with the orientation of the tensile axis in the middle of the stereographic triangle, were deformed at 293 and at 400 °K, to different degrees of plastic deformation at a strain rate ε = 6 × 10 −5 s −1 . The slip bands on the cylindrical surface of the crystals were studied by optical microscopy. At room temperature, at the beginning of deformation, a large number of slip systems with all four Burgers vectors are found to be operative. It is found that the slip planes do not correspond to those with maximum resolved shear stress, but rather to planes perpendicular to the surface. The slip bands belonging to the planes with maximum resolved shear stress are more pronounced, when the temperature and flow stress are increased; at 400 °K, in the region I, the primary slip system is dominant. These observations are explained assuming that screw dislocations have a low mobility, which can change under the influence of temperature and stress.
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