1974 · 21 citations · 0 references
EngineeringMaterials EngineeringMaterials ScienceMechanical Behavior Of MaterialsMetallic MaterialsStructural MaterialsDamage MechanicsFatigueFracture MechanicsFracture PropagationSteel MaterialsStrength Of MaterialsCrack PropagationFatigue Crack GrowthFatigue Crack PropagationFatigue FractureIntergranular FractureMicrostructureSteelsYield Strength
For low strength materials (unayial yield strength less than approximately 300 N/sq. mm), the slope of the crack propagation curve, representing data obtained from center-notched sheet specimens, may not change at the fracture mode transition. Providing the fracture path is transgranular, the rates of crack propagation in weld metals, HAZs and structural steels in the range of yield strengths 375-636 N/sq. mm are not strongly influenced by the material microstructure. The incidence of intergranular fracture causes the rate of crack propagation to increase. Tempering reduces the incidence of intergranular fracture and consequently improves the fatigue properties of the material.