Carbide-leading texture of eutectic microstructure in As-cast high chromium cast balls

Abstract

An unusual texture was observed in eutectic microstructure of high chromium cast balls. Amount of eutectic carbides, different from the eutectic austenite, were almost parallel to the cast ball surface. There were low-angle boundaries in the austenite grains or the carbide grains. It is seen that carbides have an axial nucleation mode and a lateral growth mode. Neither oriented nucleation nor oriented growth can account for the austenitic behavior individually. Really, austenite grows dependently of contiguous carbides, whose orientation is affected by both the spatial limit of contiguous carbides and the solidification temperature gradient. Finally, eutectic carbides effect the orientation of eutectic microstructure during solidification including the austenite deflection orientation.