Abstract
Rapidly solidified powder with Fe-4%C-12%Cr-13%V chemical composition was annealed at various temperatures between 150 and 700 °C. Powder specimens prepared by such a way were subjected to the microstructural evaluation, analysis of phase constitution and microhardness measurements. Mentioned characteristics were assessed as a function of both the annealing temperature and the powder particle size. It has been determined that below the temperature of 500 °C, no significant changes had commenced. Annealing at 500 °C and higher temperatures led to the metastable austenite-b.c.c. transformation and intensive fine carbides precipitation. The temperature at which the mentioned transformations start and finish and the kinetics of transformations, are closely related to the powder-particle size. Microstructural changes and phase transformations result in microhardness peak that was determined for specimens processed at 550 °C. Higher annealing temperature induces both the complete γ-b.c.c. transformation and the growth of precipitates that decreases the powder microhardness considerably.

Key words
rapidly solidified powder, annealing, γ-b.c.c. transformation, carbides, precipitation, microhardness peak

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