Viscosity of Fe-Cu melts

Abstract

We have studied composition dependences of kinematic viscosity for Fe-Cu melts with the aim of determining the temperature and composition ranges where chemically inhomogeneous Fe-Cu melts exist. Measurements were performed during heating and cooling in the temperature range from 1550 to 1700A degrees C. Evidence has been found for chemical inhomogeneity of Fe-Cu melts in the form of both microheterogeneity and a nonuniform distribution of dissimilar atoms. We have determined the temperature and composition ranges of microheterogeneity in the phase diagram of the Fe-Cu system. The nonuniform Fe and Cu distributions have been accounted for in the quasi-chemical approximation of the theory of irregular solutions, which has been used to evaluate the short-range order parameter and integral enthalpy of mixing

ON THE INFLUENCE OF SCANDIUM ON THE FLUIDITY OF THE AlMg6Li2 MELTS

“…Such inhomogeneities may be presented by particles close in composition to compounds resulted from phase analysis of 01421 alloy: S1-phase (Al2MgLi), β'-phase Al3(Sc, Zr) δ'-phase (Al3Li). It was previously established that micro-inhomogeneities of hereditary nature in Al-Sc system melts close in composition to Al3Sc compound irreversibly break down after heating of a liquid metal to 900°C [14]. According to the data of theoretical analysis of diffusion processes occurring during melting of aluminium alloys, it is most likely that the refractory inclusions Al3(Sc,Zr) remain in AlMg6Li2Sc(0-0.4) melt at temperatures above liquidus.…”

“…The overheating before the temperature determined for each composition alloy or other energetic effects on melt (e.g., ultrasound) required for of their destruction. The heating of the liquid metal to T* significantly change the crystallization will conditions, microstructure and mechanical properties of solid metal [11][12][13][14][15]. Earlier experiments found that the destruction of microscopic in homogeneities in the of aluminum melts is usually accompanied by abnormalities of the temperature dependence of the properties of the liquid metal, in particular viscosity.…”

“…Found a divarication of the temperature dependence of the melt viscosity, the corresponding modes of heating and subsequent cooling of the sample. The T* temperature at which the irreversible destruction of microscopic in homogeneities and the melt transition in the homogeneous state happening, determined by at the branching point the temperature dependences of viscosity obtained during heating and subsequent cooling of the sample [12][13][14][15].The temperature T* is called the homogenization temperature. We performed measurements of temperature dependencies of viscosity of AlMg6Li2Sc (0-0.4) to determine the temperature T*, to which the liquid alloy 01421 (5.29%Mg; 2.20%Li; 0.06%Mn; 0.14%Si; 0.11%Fe; 0.15%Zr; 0.21%Sc; the rest is aluminum) is heated before casting and crystallization in order to destroy micro-inhomogeneities of hereditary nature.…”

Atomic transport properties and liquid–liquid phase separation of ZnxBi 1−x liquid monotectic alloys

“…But the experimental data above the critical temperature (T = 873 K) do not show any such feature for Zn x Bi 1−x monotectic alloys. Chikova et al performed measurements for the kinematic viscosity for liquid Fe-Cu alloys at 1550, 1640 and 1670 K [18]. Their data recorded during heating and cooling show downward bending at three different locations and looks like a wavy pattern across the whole concentration range.…”

“…the viscosity and the diffusion coefficients are different in different materials even in the same thermodynamic state [4][5][6][7][8][9][10][11][12][13]. We note here that many researchers performed measurements to understand the transport behaviour of liquid metallic systems (see [14][15][16][17][18][19][20][21] and references therein) and some model calculations are also available [22][23][24][25].…”