Phase strength effects on chemical mixing in extensively deformed alloys
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.
- Publication:
-
Acta Materialia
- Pub Date:
- January 2015
- DOI:
- 10.1016/j.actamat.2014.09.009
- Bibcode:
- 2015AcMat..82..123C
- Keywords:
-
- Mechanical alloying;
- Non-equilibrium solid solutions;
- Powder processing;
- Kinetic Monte Carlo;
- Alloy design