Assessment of grain refinement by microtexture analysis in thermomechanically processed Al 2519 alloy

Abstract

The first part of this study involved determining the mechanism by which elevated-temperature deformation occurred for selected tensile specimens from previous research on thermomechanically processed Al2519 alloy. Microtexture information in the form of discrete pole figures indicated that the most highly superplastic material had completely recrystallized and deformed via grain boundary sliding, whereas material that did not display superplastic behavior deformed via slip. The second part of the study was designed to achieve further refinement of the microstructure of Al2519 using the particle stimulated nucleation (PSN) model as a guide. Using the overaging parameters of the thermomechanical process (TMP) that had yielded the greatest elongation in previous work, additional material was processed but with varying final total processing strain. The resulting material was analyzed using backscatter electron (BSE) microscopy methods to evaluate the effect of total processing strain on the average grain size. The smallest true volume grain size was associated with the material with the highest total processing strain. jg p3.