Dynamic SIMS study of Cr C , Cr C and Cr C 3 2 7 3 23 6

Dynamic SIMS using 4-keV Xeq has been performed on Cr3C2, Cr7C3 and Cr23C6 in order to determine if SIMS might be useful in distinguishing between these Cr carbides with different compositions. The positive and negative ion patterns consist of Cr C ions, and the yields have been normalized using the Crq and Cry signals, respectively. Even though the p n stoichiometric Cr-to-C atom ratios are significantly different for these three Cr carbides, the normalized negative and positive ion patterns are quite similar, and observed differences do not correlate in a straightforward manner with compositional differences. These data indicate that the surfaces formed during sputtering are similar for the three compounds. q1998 Elsevier Science B.V. All rights reserved.