Characterization of Stainless Steel SUS304 Modified by KrF Excimer Laser Implant-Deposition and Its Properties after the Thermal Treatment

Abstract

The characterization of structural and chemical properties of stainless steel (SUS) 304 modified by laser implant-deposition (LID) of Si using a KrF excimer laser has been investigated. The cross sectional transmission microscope (X-TEM) observation and X-ray diffraction (XRD) measurement suggest that LID technique can form the top of the Si deposited layer and the interdiffusion layer between Si and SUS304. In addition, the compounds between Si and Fe such as Fe₃Si and FeSi₂ are formed in the interdiffusion layer. Under the thermal treatment of 600°C for 1 hour in the N₂ atmosphere, the interdiffusion coefficient is as small as - 2.0 × 10^-15cm²/s, which is six orders of magnitude smaller than that in the SUS304 deposited on Si by electron beam evaporation. Additionally, the corrosion property of LID-modified SUS304 against an HCl aqueous solution has no remarkable change after the thermal treatment in spite of the deterioration of the characteristics in the EB-evaporated SUS304. Thus, the LID-surface modification can provide the high corrosive properties even if the exposed after the thermal treatment.