Precipitation modeling for prediction of the evolution of acoustic nonlinearity in an iron–copper alloy

Abstract

Computational precipitation modeling tools are used to predict the nucleation and growth of copper precipitates in a Fe–1%Cu alloy isothermally aged at 500 °C up to 500 h. The size distribution is used to predict the classical material nonlinearity (β) of the alloy utilizing two existing physics-based models that relate the change in nonlinearity Δβ to the interaction of dislocations with coherency strains that develop around growing precipitates. The Δβ modeled qualitatively matches the increase in β observed experimentally. However, the precipitation model underpredicts precipitate radii measured in previous experimental work, resulting in an underprediction of Δβ.