Shock Temperature Measurement for Metals－Influences of a Gap Interface between the Driver Plate and the Metal Film Sample on the Shock Temperature Measurement by Using Radiometry

Radiometry is one of the most commonly used techniques in shock temperature measurement for metals. In this paper, we investigated the thermal relaxation history at the sample/window interface for a widely used four-layer target-sample configuration of the metal drive/gap/metal film/transparent window system, and its influence to shock temperature measurement of metals. Although there does not exist a universal analytical solution for the thermal conduction equation of such a four-layer model, an analytical approximation solution does exist, which indicates that the thermal relaxation at the sample/window interface following the shock compression is closely related with the dimension of the gap. If the width of the gap can be compared with the thickness of the film, a sharp peak will appear at the initial of the step-like temperature profile of the sample/window interface, the height and the width of the peak are closely connected with the dimension of the gap. On the other hand, if the thickness of the metal film is much greater than that of the gap, however, a stepped temperature interface with a flat top will appear. Necessary conditions for which a reasonable target-sample assembly should meet with are also discussed.