Exploration of laser-driven X-ray backlighting applied in research of micro-spalls of metal target

Micro-spall problem of shock-melted materials is an important scientific issue in shock physics. This paper examines the application of the advanced laser-driven X-ray backlighting technique in the study of this problem. High energy laser beams were launched by SGⅡ to drive the aluminum physical target and the copper backlighting target. The X-ray emitted from the backlighting target was directed to pass through a pinhole to take the radiograph of the microspall products. High-quality radiograph was finally obtained, whose spatial resolution was found to be greater than 40 m via the examination of standard grids. Moreover, the radiograph shows clearly the products can be divided into different regions, which directly reveals different mechanism of the fragmentation of the target. The success of our exploring experiments demonstrate the prospect of the application of the technique in the micro-spall study.