The phase and microstructure changes in 45# steel irradiated by intense pulsed ion beams

Intense pulsed ion beam (IPIB) treatment is a new technology of surface mod ification. Compared to traditional ion implantation, the intense pulsed ene rgy effect takes the main role in the IPIB modification processes. Therefor e, the phase and microstructure changes induced by IPIB irradiation is much stronger than those induced by traditional ion implantation. We investigat ed the phase and microstructure changes in surface layer of 45(#) steel sam ples irradiated with intense pulsed ion beams at different pulsed energy de nsities by transmission electron microscopy (TEM), scanning electron micros copy (SEM) and X-ray diffraction (XRD). The nanohardness distribution in a cross-section of the sample surface layer was also measured. The ferrite an d laminated pearlite structures in near surface layer was changed in differ ent degrees that grow with the pulsed energy density. The depths of these m odified layers are much deeper than the ion range. Polished surfaces of sam ples were roughened with 10 mu m-scale width and 1 mu m-scale depth craters . The results of above analyses are discussed. (C) 2000 Elsevier Science S. A. All rights reserved.