Journal of Applied Physics · 1951 · 84 citations · 3 references
EngineeringMaterials EngineeringMaterials ScienceMechanical Behavior Of MaterialsMetallic MaterialsMetallurgyDamage MechanicsExplosion HazardsFracture MechanicsFracture PropagationImpact MechanicsShock WavesBlast ImpactBlast-induced DamageBlast-induced StressBlast-induced Stress WavesCompressional StressPhysical PropertiesStress Wave PropagationWave-induced Stress
Fracturing of a material near a free surface caused by a high‑intensity compressional stress wave has been noted for years, yet quantitative links between the fracture, the stress‑wave characteristics, and material properties are scarce. The authors examined five metals (1020 steel, 4130 steel, 24S‑T4 aluminum alloy, brass, and copper) by detonating an explosive charge to generate a high‑intensity stress wave and measured its pressure distribution with a modified Hopkinson‑bar experiment. Scabbing is primarily governed by the spatial pressure distribution within the wave and a material‑specific critical normal fracture stress σc, whose numerical values were determined for each of the five metals.
Fracturing, or scabbing, of a material near a free surface as the result of a transient compressional stress wave of high intensity impinging on that surface has been observed for many years; however, little quantitative data that relate the fracture to the nature of the stress wave and the physical properties of the material seem to exist. The phenomenon has been investigated for five metals, 1020 steel, 4130 steel, 24S-T4 aluminum alloy, brass, and copper, by using an explosive charge to induce a high intensity stress wave in the metal. The distribution of pressure within the wave was determined by a modified Hopkinson-bar type of experiment. Scabbing has been found to be governed principally by the spatial distribution of pressure within the wave and a critical normal fracture stress σc that is characteristic of the material and perhaps the state of stress. Numerical values of σc were obtained for each of the five metals.
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