Carbon atoms segregate in the surface region for polished AISI 440C stainless steel After ion implanta tion, the surface carbon atoms exist in different forms. To elucidate their existence, surface structures and carb...Carbon atoms segregate in the surface region for polished AISI 440C stainless steel After ion implanta tion, the surface carbon atoms exist in different forms. To elucidate their existence, surface structures and carbon chemical states o[ unimplanted, N~ implanted, Ti＋ implanted and N＋/Ti＋ co-implanted samples were analyzed by X-ray diffraction （XRD）, transmission electron microscopy （TEM） and X-ray photoelectron spectroscopy （XPS）. The results indicated that various phases form in the surface or subsurface region after ion implantation, while the surface topography of the samples remains intact. For polished unimplanted sample, besides some Fe3 C phase and C- C phase, Cr, Cs phase dominates its surface region. Little change of carbon chemical states occurs after N＋ ion im- plantation. For Ti＋ implanted sample, besides some metal oxycarbide phases, most carbon amorphous phases form in surface region. Concerning N＋/Ti＋ co-implantation, CrrCs compound as well as Fe^C phase dominates the sur face region while no C-C phase is found. In addition, compared with single ion implantation, N＋/Ti＋ co-implanta tion would increase the ion implantation depth significantly. The formed phases of the carbon atoms play an impor- tant role in affecting the surface properties of AISI 440C stainless steel.展开更多
基金Sponsored by National Natural Science Foundation of China(51075004)Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality(PHR201107109)Importation and Development of High-caliber Talents Project of Beijing Municipal Institutions(CIT&TCD201304005)
文摘Carbon atoms segregate in the surface region for polished AISI 440C stainless steel After ion implanta tion, the surface carbon atoms exist in different forms. To elucidate their existence, surface structures and carbon chemical states o[ unimplanted, N~ implanted, Ti＋ implanted and N＋/Ti＋ co-implanted samples were analyzed by X-ray diffraction （XRD）, transmission electron microscopy （TEM） and X-ray photoelectron spectroscopy （XPS）. The results indicated that various phases form in the surface or subsurface region after ion implantation, while the surface topography of the samples remains intact. For polished unimplanted sample, besides some Fe3 C phase and C- C phase, Cr, Cs phase dominates its surface region. Little change of carbon chemical states occurs after N＋ ion im- plantation. For Ti＋ implanted sample, besides some metal oxycarbide phases, most carbon amorphous phases form in surface region. Concerning N＋/Ti＋ co-implantation, CrrCs compound as well as Fe^C phase dominates the sur face region while no C-C phase is found. In addition, compared with single ion implantation, N＋/Ti＋ co-implanta tion would increase the ion implantation depth significantly. The formed phases of the carbon atoms play an impor- tant role in affecting the surface properties of AISI 440C stainless steel.
