Texture development during grain growth in polycrystals with strong preferred orientation

Abstract

Texture alterations accompanying grain growth have been simulated by means of a new statistical model which for the first time takes into account the dependence of both the energy and mobility of grain boundaries on their disorientation. Model polycrystals with a single-component texture are assumed to consist of preferably oriented grains A (the main texture component) and randomly oriented grains B. Therefore, there are three types of grain boundaries in these polycrystals: high-angle A–B and B–B boundaries, and A–A boundaries with a smaller disorientation. A novel map showing the effect of both the scatter and intensity of the main texture component on the character of grain growth is obtained. Abnormal grain growth leads eventually to vanishing of the main texture component. However, the main component enhances at the incubation period of abnormal grain growth, especially in the case when the initial distribution of randomly oriented grains is displaced toward small sizes, as in materials with cube texture. The texture evolution during normal grain growth is strongly affected by the initial position of the size distribution of randomly oriented grains. If this distribution is displaced toward small sizes, the main texture component is enhanced. In contrast, normal grain growth results in vanishing of the main component if the initial size distributions of grains A and B are identical. Various texture evolutions observed in the simulations are shown to be a result of an interplay of the consumption and the growth of randomly oriented grains during the growth process.