Mass ejection from shock-loaded free surfaces of steel

Abstract

The mass ejection from shock-loaded free surfaces of steel specimens under several condition of machining were measured using the piezoelectric quartz crystal gauge technique. At shock pressure of 45 GPa, the ejected mass quantities of steel with respect to the surface smooth finishes 0.4 μm (machinework) and 0.11 μm (vibration- roll compression) are 0.2 g/m² and 0.15 g/m², respectively. The ejected mass quantities of steel with respect to the surface smooth finishes 0.2 μm (polishing) and 0.1 μm (abrasiveness) are very small. Experiments show that the mass ejection is dependent on conditions of free surfaces. Surfaces defects, such as pits, scratches and machine marks are thought to be the primary reason for mass ejection.