Possibilities of the Materials Properties Improvement for the Cementite Eutectic by Means of Unidirectional Solidification

Abstract

The paper brings the results of directional solidification of Fe-Fe 3 C eutectic alloy. The Bridgman method with vertical thermal gradient in conducted research was applied. Two values of rate was used for sample movement testing. One sample after solidification, was immediately taken of the cooler. The distribution of thermal gradient in the alloy was determined. The value of thermal gradient in liquid at the solidification front was determined. On the samples, where cementite eutectic was oriented, interphase spacing λwas measured. The results of the dependence between parameters v and λ were presented. The research with application of optical microscope and computer programme to image analysis NIS-Elements was used.Keywords: ledeburite, directional solidification, eutectic, structure, interphase spacing W pracy przedstawiono rezultaty kierunkowej krystalizacji stopu eutektycznego Fe-Fe 3 C. Wykorzystano metodę Bridgmana z pionowym gradientem temperatury. Zastosowano dwie prędkości przemieszczania próbki. Jedna z próbek, po zrealizowaniu krystalizacji została zamrożona. Określono rozkład gradientu temperatury w stopie oraz wyznaczono wartość gradientu temperatury w cieczy na froncie krystalizacji. Na próbkach przeprowadzono pomiary odległości międzyfazowej λ. Przedstawiono wyniki badań określających zależności pomiędzy parametrami v i λ. W badaniach wykorzystano mikroskop optyczny oraz program do komputerowej analizy obrazu NIS-Elements.

Solidification Front of Oriented Ledeburite

“…Then the sample was frozen (immediately taken off the cooler). This is described in more detail in [12,13].…”

Solid-liquid interface morphology of white carbide eutectic during directional solidification

“…The sample was grown by pulling it downwards at a constant pulling rate v = 125 μm/s (450 mm/h) and at a constant temperature gradient G = 33.5 K/mm by means of motor. This is described in more detail in [15]. After the sample was moved by 2/3 of its length it was frozen.…”

Thermodynamic Prediction Of The Diffusion Barrier Morphology In The Al/Ni – Nano-Foil Designed For The Self-Propagating Reaction

“…Moreover, the barrier solidification is directional process which can result in the improvement of the material properties, [11].…”