Abnormal grain growth development from uniform grain size distributions

Abstract

The development of abnormal grain growth from uniform grain size distributions pinned by particles is examined. The main assumption is that a locally lower pinning force adjacent to a large grain can cause this grain to grow abnormally. The case of a matrix pinned by unstable particles is considered in detail. A quantitative criterion is derived which shows the interplay among the variables involved. From this it is shown how both deterministic and probabilistic factors contribute to abnormal grain growth. Practical implications are discussed with particular emphasis on why abnormal grain growth can be so difficult to control. The present treatment offers a new and plausible rationale for the development of abnormal grain growth from uniform grain size distributions containing unstable particles.