Changes of stainless steels surface morphology as a result of interaction with intense pulsed plasma beams containing ions of rare earth elements

Among different methods used in surface engineering such as CVD, PVD, ion implantation etc., the techniques using high intensity ion or plasma beams are relatively new ones. The results reported thus far show that the treatment of steel surface with high intensity plasma pulses can lead to changes of its morphology and mechanical properties. Stainless steels have very good corrosion resistance, but they have low hardness and poor tribological properties. The intense pulsed plasma beams were used for modification of alloyed steels especially austenitic (1.4301 and 1.4401) and ferritic (1.4016) stainless steels with various content of alloying elements. Samples were irradiated with 2, 5 or 10 short (μs scale) intense (density of energy was about 5 J/cm2) pulses. Heating and cooling processes were of non-equilibrium type. In all samples the near surface layer of the thickness in μm range was melted and simultaneously doped with cerium and lanthanum. The aim of this work was to investigate the changes of stainless steel surface morphology after melting, rare earth elements (REE) addition and rapid solidification after interaction with intense pulsed plasma beams. The surface morphology was analyzed using a scanning electron microscopy (SEM) technique. Changes of surface roughness were determined by profilometric measurements. The efficiency of REE addition process was also determined.