Experimental study of micro-spalling fragmentation from melted lead

In this paper, we conduct an experimental investigation of a Pb target shocked using high explosives through the use of an improved, non-radiographic diagnostic technique called an Asay window. In the case considered, the Pb sample is melted upon release at a shock-breakout pressure of about 38 GPa. By converting the measured velocity profile of an Asay window, the mass and density distributions as a function of spatial distance in the melted Pb sample were quantitatively obtained at different offsets, corresponding with the formation of micro-spalling fragments. The physical analysis is in reasonable agreement with the result for an Sn sample recorded by proton radiography