Vを含むMn-Cr系オーステナイト鋼の析出挙動

抄録

The precipitation behaviour of V₄C₃ and the structural change in Mn-Cr-V type austenitic steel with a chemical composition of 0.44%C, 17.40%Mn, 12.15%Cr and 2.37%V have been studied by measuring the changes in dilatation and hardness and by transmission electron microscope observations. The results obtained are as follows:
(1) The precipitated carbide which brings about a remarkable hardening and dilatation change is spherical V₄C₃ only.
(2) The strain field caused by the coherency between V₄C₃ and the matrix is released when the particle size grows up to a diameter of 150∼160 Å, resulting in contraction and the hardness decrease of the austenic steel. This suggests that the coherency between V₄C₃ and the matrix plays an important role in the strengthening of austenitic steel in the Mn-Cr-V system.