Characterization of precipitation in Al-Mg-Cu alloys by X-ray diffraction peak broadening analysis

The present study examines the aging behavior of Al-Mg-Cu alloys based on the elastic effects on the matrix due to coherent precipitates; these effects were followed by X-ray diffraction peak broadening analysis. We conclude that the growing of matrix distortion zones around the precipitates is well described by the 2M factors established by Houska. In terms of mechanisms, in the first stages of ageing the rapid hardening seems to not be related with the interaction of dislocations with the stress field around the precipitates. The incremental microhardness observed in this alloy can be attributed to the formation of clusters or to solute-dislocation interactions.