Comments on “Effects of X (V, W, Mo, Hf, Ta, Zr) additions on the ideal cleavage fracture of Cr2Nb: First-principles determination” [Intermetallics 18(2010)65–69]

In the paper of Chenliang Li and Biao Wang et al. it is concluded that V on Cr sites and X (W and Zr) on Nb sites can increase the cleavage strength of Cr2Nb, while X (W and Mo) on Cr sites and X (Mo, Ta and Hf) on Nb sites can reduce the cleavage strength of Cr2Nb, which results are consistent with available experimental ones. However, a comparative analysis of these data with experimental data clearly shows that the computational model has shortcomings such that it may be invalid. As an alternative route, some results based on experimental data are supported to suggested accurate computational method model and comparative results. Further data on fracture strength are added.