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Summary The microstructures of the Fe–Cu‐based alloys melt‐spun from various temperatures are presented. Two compositions, with different Fe and Cu content, revealing liquid miscibility gap, were studied. Nonuniform, large‐elongated areas were observed for lower melt‐spinning temperatures, indicating liquid/liquid phase separation in the crucible before cooling. An increase of the melt ejection temperature, followed by rapid cooling, brought about precipitation process within homogeneous melt. Studies of the system with higher Fe content proved amorphous nature of the matrix and crystalline structure of the primary formed Cu‐rich precipitates. Moreover, generations of the secondary spherical particles, precipitated within the previously formed Cu‐rich melt, were observed. The microstructure of the melt‐spun alloy with a higher Cu content, on the other hand, consisted of the Fe‐rich amorphous spherical particles formed during cooling of the Cu‐rich liquid. The precipitation of the secondary Cu‐rich particles in the primary formed Fe‐rich was also observed.

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A thermomechanical finite-element model of flat rolling is coupled with closed form equations describing the process of recrystallization and is applied to study hot rolling of low carbon steel strips. Formulae for the recrystallized grain diameters, developed by various authors, are considered. Calculated diameters of the grains are compared with the results of the measurements carried out after experimental hot rolling of the carbon steel samples. Evaluatingthe accuracy of the calculations. using each of the expressionsfor the diameter of the recrystallized austenite grains, indicates that the relation of Roberts is closest to the measurements. Ausbildung der Mikrostruktur beim Warmwalzen. Ein thermomechanisches Finite-Elemente-Modell, das beim Flachwalzen bekannt lst, wird mit analytischen Gleichungen, die die Rekristallisation beschreiben, gekoppelt. Das resultierende System soli Aussagen Ober das GefOge nach dem Warmwalzen von kohlenstoffarmem Bandstahl zulassen, Beziehungen fOr die Korndurchmesser nach Rekristallisation von verschiedenen Autoren werden diskutiert. Die berechneten Korndurchmesser werden mit Werten verglichen, die an warmgewalzten Stahlproben gemessenwurden. Die Auswertung der Genauigkeit dieser Rechenmodelle zeigt, daB die Beziehung von Roberts die Verhaltnisse am besten wiedergibt.