Influence of Grain-Boundary Character on the Cellular Precipitation in a Ni-Sn Alloy

Abstract

The Relation between the formation and growth of grain-boundary cells at each individual grain-boundary and the character (Σ value) of its boundary in a Ni-16 mass%Sn alloy on aging at 823 K after quenching from 1273 K was investigated by means of SEM-ECP measurement and optical microscopic observation.
The formation and growth of cells at CSL boundaries with low Σ values were suppressed as compared with those at random boundaries (Σ≥31). Especially, no cells were observed at twin boundaries (Σ=3). However, at some of the random boundaries, cells were scarcely observed. This fact suggest that the formation and growth of cells relate not only to the Σ value of the grain-boundary but also to the inclination of the boundary and the grain-boundary structure (atomic arrangement in the grain-boundary).