4-1-5强度、断裂及断裂韧性 Strengt th, Fracture and fracture Toughness of Materials Strengt stress(tensile, compression and shear flexural, torsional and impact fracture Brittle fracture Theoretical fracture strength Ductile fracture with a plastic deformation Transition of Brittle and ductility Fracture Toughness4-1-5 强度、断裂及断裂韧性 Strength, Fracture and Fracture Toughness of Materials Strength stress(tensile,compression and shear) flexural, torsional and impact Fracture Brittle Fracture, Theoretical fracture strength Ductile Fracture with a plastic deformation Transition of Brittle and Ductilty Fracture Toughness