Misorientation effects on discontinuous precipitation in Al-Ag-Ga

摘要

The aim of the work is to elucidate the mechanisms of discontinuous precipitation (DP) in an Al-2.8at/100 Ag-1 at./100 Ga alloy, which has a relatively small coherency strain energy. Besides in situ TEM investigations, microtexture measurements were carried out using the EBSD technique. Characteristic Misorientation relationships (25 deg-40d deg{<115> and<332>}) were found between grains with a propensity for Discontinuous precipitation. This is attributed to the anisotropy of interface boundary energy, as first Pointed out by Tu and Turn bull(Acta Metallurgica, 1967, 15m 369). The interpretation is supported by Particle-boundary orientation relationships revealed in the TEM at the incipient stages of DP.