Wave Formation between Impacting Liquids in Explosive Welding and Erosion

Abstract

IN a study of impacting liquid sheets using high speed photography, we have observed the development of a wave pattern along the interface between the colliding liquids. The waves were similar to those reported in other studies on impact, notably in explosive welding of metal plates¹, in ballistic impact^2,3 and in the erosion of metal surfaces under the high speed impact of liquid drops⁴. Explanations concerning the wave patterns found in these investigations have been based on a study of the deformed and wavy surface after impact. Serious practical difficulties have usually prevented observation of the collision interface during the event. The technique to be described, however, has just this advantage, namely that waves can be observed to form during the impact. The fact that the collision occurs at low velocities between liquids need not seriously detract from the usefulness of the model. In the more extreme conditions of high velocity impact with solids, the impact pressure is sufficiently high compared with the flow stress of the solid that the problem is treated hydrodynamically anyway.