In order to test the ability of this model (and the NIKE-2D code) to simulate a hardness test, comparisons were made to previous simulations by Bhattacharya and Nix (1988a,b), who also compared their simulations to experimental hardness measurements. Hence, there is an implicit comparison to experimental results here. First, comparisons were made for the case of the hardness testing of a homogeneous material, using selected properties from Bhattacharya and Nix (1988a). This previous work used a different code (ABAQUS), so it provides an independent test of NIKE-2D's ability to model hardness tests. The results from this simulation agreed with those from previous simulations, within the error estimates established in the next section. In order to verify the ability of NIKE-2D to simulate specimens for which the yield stress varies with depth, comparisons were made to the results in Bhattacharya and Nix (1988b), in which the hardness of coatings are simulated. Again, comparison of results from NIKE-2D to results from previous analyses agreed within the expected error. Hence, NIKE-2D is capable of simulating hardness testing in both homogeneous and coated materials. The author is not aware of any previous simulations of ion-implanted materials.