Studies of the formation and distribution of cracks and various defects on the heated tungsten plate surface during pulsed plasma flux impact

Abstract

In this work, cracking of the surface of a tungsten plate was studied using a PW-7 pulsed plasma accelerator. The surface of the tungsten plate was exposed at an energy density and plasma flux duration of 1.1 MJ/m2 and 200 μs, respectively. Before each shot, the base of the tungsten plate was heated to a temperature of 823 K. Heating of the base of the tungsten plate above the ductile–brittle transition temperature made it possible to control the temperature gradient on its surface under pulsed plasma exposure. In other words, the temperature gradient of the tungsten plate before and after exposure to the plasma flux decreased. Compared to the data at room temperature, the results of heating of the tungsten plate to the tungsten ductile–brittle transition temperature of 823 K showed a reduction in crack width to several hundred nanometers under the influence of plasma. It should be noted that heating of the plate did not completely eliminate cracking of the surface of the tungsten plate. However, this significantly minimizes the emission of dust from the surface of the tungsten plate under the influence of the plasma flux (barely no dust was observed).