A NEW DISCUSSION OF THE INTERACTION ENERGY IN THE SOLID-SOLUTION HARDENING OF BCC IRON-ALLOYS

The Suzuki theory describes the substitutional solid solution hardening of body centered cubic (b.c.c.) crystals using the interaction energy E(w) between the screw dislocation core and the solute atom. E(W) is usually estimated from the dependence of lattice constants and isotropic shear moduli on the concentration of solute atoms. To improve the physical understanding of E(w), it is discussed here which modulus would be adequate to this special problem. Those elastic constants which are correlated with the actual distortion field around the screw dislocations are to be preferred. The yield stresses of at least six iron based alloy systems can be described satisfactorily in this way.