The chromium thin films were prepared using ion beam deposition on stainless steel 304. The chromium films were implanted by nitrogen ions after deposition at doses in the range of 4.5 x 10(17) to 2.7 x 10(18) N+/cm(2) and energy of 30 keV. The formation of nitride phases and corrosion behavior after nitrogen implantation were characterized by XRD and corrosion test, respectively. The results show that corrosion resistance rise, reach to a maximum at dose of 1.8 x 10(18), and then fall down at higher doses. In addition, the effect of corrosion tests was analyzed using scanning electron microscopy (SEM). (c) 2005 Elsevier B.V. All rights reserved.