AUSTENITE STABILIZATION OF Fe-Ni ALLOY

By X-ray powder diffraction and magnetometric methods we investigated the effect of phase hardening during γ-α-γ transitions. In this case austenite becomes more stable to subsequent γ-α-γ transitions, the dislocation density increases, the grain reduce in fragments and the hardness increases, too. In addition, the γ-solid solution in some steels is unstable during ageing. The phase hardening was found to stabifize the γ-solid solution of Fe-Ni alloy to subsequent thermal treatment. This is consistent with an increase in carbon mobility after γ-α-γ transitions. Tlat is why decarbonizations of austenite iake place during increase in extent of phase hardening. PACS numbers: 61.10.Lx, 61.50.Ks