The influence of the grain size of microstructure of the surface layer material of a hypersonic body on the properties of air plasma

The flight of hypersonic bodies in the air is accompanied by intense processes of gas and body surface heating, its erosion and ablation. At the same time, temperature near the body surface and the intensity of these processes are higher, for greater density and pressure of the environmental gas. The results of experimental investigations of properties of low-temperature air plasma initiated in air by the movement of hypersonic bodies with velocities close to the first cosmic velocity are presented. To intensify the processes and for studying the characteric features of the flight in extreme conditions, the model experiments were conducted in air in the normal initial state. The technique of X-ray and mm-wave diagnostics of plasma properties and microstructural analysis of hypersonic body material were utilized in the experiments. 1 The paper was presented at 10th Electromagnetic Launch Technology Symposium, April 25-28, 2000, Renaissance Parc 55 Hotel, San Francisco, California, Book of abstract, p.160.