Comparative Analysis of 3%Cr Roller Steel by Rare Earth Refining and Electroslag Remelting

Abstract

3% Cr roller steel produced by two smelting process routes of the electroslag remelting and the rare earth refining respectively was studied， the chemical composition difference， microstructure， the characteristics of inclusion， as well as mechanical properties for these two roller steels were comparatively investigated by SEM， EDS， ASPEX etc characterization means and experimental methods of electrolysis extraction， tensile， impact tests etc . The results showed that w［Ce］ ≤0.01%， w［Al］ =0.022%， and w［Al］ =0.018% in the rare earth refined roller steel， and the two processes have similar control levels on the impurity elements in the steel. After heat treatment with the same process， there was similar microstructure of the tempered sorbite in these rare earth refining and electroslag remelting roller steel， and microstructure uniformity of roller body made by two processes was almost consistent. The inclusions in the rare earth refined roller steel are mainly ellipsoidal CeAlO3 and Ce2O2S the average size is about 4.17 μm， and the area percentage is about 0.0066%；Meanwhile some irregular Al2O3 particles about 3.88 μm in average diameter in the electroslag remelting roller steel were also observed about 0.008 1% in area fraction. Moreover， the yield strength of rare earth refining roller steel were few different from those of the electroslag remelting roller steel. But the elongation， area reduction and impact toughness of the rare earth refining roller steel were higher than those of the electroslag remelting roller steel.

Keywords

• roller steel； rare earth refining； electroslag remelting； non-metallic inclusion； mechanical properties