Influence of high-intensity pulsed ion beams irradiation on corrosion resistance of stainless steel
The surface of 316L stainless steel was treated by high-intensity pulsed ion beams(HIPIB).The influence of the HIPIB irradiation on the electrochemical corrosion resistance of 316L stainless steel in 0.5 mol/L H2SO4 was investigated.The polarization curves show that the corrosion resistance of the irradiated specimens can be improved markedly, and the free corrosion current depends more on the shot number of HIPIB than the free corrosion potential.The surface morphology and the phase structure in the near surface region of the original and the treated specimens were analyzed with scanning electron microscopy and X-ray diffraction.Electron probe microanalysis was used to study the distribution of elements on the irradiated specimens. It is found that the HIPIB irradiation can smooth the surface of the targets,and preferred orientation occured in the surface layer of the treated specimens.Otherwise,selective ablation of impurities occurred during the interaction between HIPIB and the targets.All of these factors result in the improvement of the electrochemical corrosion resistance of 316L.