Phase strength effects on chemical mixing in extensively deformed alloys

TitlePhase strength effects on chemical mixing in extensively deformed alloys
Publication TypeJournal Article
Year of Publication2015
AuthorsCordero, ZC, Schuh, CA
JournalActa Materialia
Volume82
Pagination123 - 136
Date Published2015/01/01/
Abstract

Forced chemical mixing during extensive straining requires that the constituent phases co-deform, and is therefore a sensitive function of their mechanical properties, particularly strength. To develop a quantitative understanding of such phase strength effects on co-deformation and steady-state chemical mixity during severe deformation processing, we studied several tungsten transition metal couples with a range of differences in strength during a process of mechanical alloying in a high-energy ball mill. Changes in the powders' microstructures, mechanical properties and chemical mixing revealed two distinct behaviors: alloys either chemically homogenized or remained dual phase, depending on the relative strengths of the base alloying elements. A kinetic Monte Carlo simulation of mechanical alloying that accounts for a phase strength mismatch reproduced the experimentally observed behaviors, and provides quantitative insight into the combination of material and processing parameters that control mechanical mixing.