Effect of Feed Rate on Texture Evolution of 42CrMo Casting Blank During Hot Ring Rolling

Abstract

The compact casting-rolling technique is an advanced method to produce seamless ring parts. The technique has been paid much attention in recent years. To find out the textual evolution rule of materials in this compact process, hot ring rolling of 42CrMo casting blank was conducted at different mandrel feed rates. The macro-textures of the as-obtained products were studied by X-ray diffraction, and micro-textural associated grain orientations were examined by electron backscattered diffraction techniques. The dominant textures in hot-rolled rings were similar, with γ-fibre consisted of {111}<110> and {111}<112> orientations as the most intense components. The α-fibre and ε-fibre textures in the entire thickness of hot-rolled rings did not show significant change as feed rate increased. Moreover, shear textures, including Copper-type {112}<111> and Goss {110}<001> components were presented in different regions of hot-rolled rings. The grain refinement was found closely related to grain orientation and micro-texture evolution in the entire thickness. The inhomogeneous distribution of grain size in the hot-rolled ring at a higher feed rate resulted in poor plasticity and toughness, which was caused by inhomogeneous γ-fibre orientations, especially in the center layer of the ring. Overall, these findings look promising for future studies dealing with compact hot ring rolling processes.