Stability of BCC transition metals under hydrostatic loading

The structural stability and theoretical strength of BCC transition metals Cr, Mo and W under hydrostatic loading have been investigated by combining the modified analytical embedded atom method (MAEAM) with modified Born stability criteria. For all three BCC transition metals Cr, Mo and W, the stable regions are controlled by shear modulus μ only. Determined stable regions are 0.917-1.079, 0.907-1.090, 0.904-1.095 in the relative deformation a/a0 and corresponding compressive and tensile theoretical strengths are 161.0 and 28.15, 162.3 and 34.56, 198.8 and 41.60 GPa for Cr, Mo, W, respectively. The calculated stresses are consistent well with the results of ab initio calculation.