Abstract

Relationships between structure-sensitive macroscopic properties and the grain boundary network are known to depend upon the intrinsic variability of the local physico-chemical properties of the boundaries and upon how these are distributed and connected in the network. Progress towards acquiring a data base linking the local properties of grain boundaries with their geometrical character (lattice misorientation and inclination) has been hampered by the rate at which grain boundary structure can be experimentally determined, by the opacity of polycrystalline materials, and by the very large number of physically distinctive (geometrical) characteristics of grain boundaries which occur in nature.Described in this paper is a perspective on modern opportunities to solve the comprehensive inverse problem relating the thermodynamic properties of grain boundaries to their geometrical type over the full (five-parameter) fundamental zone. The advent of rapid, automated measurements of local lattice orientation (orientation imaging microscopy), when coupled with precision serial sectioning, makes it feasible now to characterize the local crystallographic and geometrical features of very large numbers of grain boundaries and triple junctions. Such data can be analyzed within a classical framework in order to extract the thermodynamic properties mapping. This paper examines the opportunities and challenges associated with the requisite measurements and analysis.This paper is dedicated to the memory of Professor Hsun Hu, whose kind encouragement and penetrating insight has inspired and lifted a generation of young scientists.