Study of craters formed on surface of AISI 321 stainless steel after high power ion-beam exposure

Abstract

Surface topography and elemental composition of craters formed on the surface of AISI 321 stainless steel after processing with powerful pulsed flows of Cn+ and H+ ions (accelerating voltage: 250 keV, pulse duration: approximately 100 ns) are studied. Processing is performed using single-pulse fluences of 1 and 3 J/cm2, with the number of pulses ranging from 1 to 50. It is determined that the average size of the craters increases and the number of craters decreases with an increase in the number of impact pulses. The average size and number of craters are not dependent on the degree of preliminary deformation of the samples. Based on the applied processing parameters, it is established that titanium sulfide or titanium carbosulfide inclusions are the preferred crater sites. Furthermore, the crater structure is examined through electron backscatter diffraction analysis. The structure and phase composition of the craters formed on steel as a result of exposure to a pulsed ion beam do not differ from the structural-phase state of the crater-free regions.