화학공학소재연구정보센터
Thermochimica Acta, Vol.445, No.2, 104-110, 2006
Enthalpy, heat of fusion and specific electrical resistivity of pure silver, pure copper and the binary Ag-28Cu alloy
Within the present work, recent investigation carried out with a fast pulse-heating technique on silver, copper and the Ag-28Cu binary alloy in the solid and the molten states are presented. Properties like enthalpy or electrical resistivity of a pulse-heated sample can be obtained for a wide temperature range (solid state up into the liquid state) from the directly measured base quantities, namely: current through the sample, voltage drop across the specimen and pyrometric determined temperature. As a further result, enthalpy of fusion is computable from the enthalpy values at the melting transition or the solidus/liquidus transition. These thermophysical properties (mainly of the melting transition and the subsequent liquid phase) are commonly used as input data for numerical casting simulations. The measurements presented within this work deal with group(1) 11 elements silver, copper and the binary eutectic 72-28 (wt.%) alloy of the two elements, respectively. One of the main goals of this work is to investigate to which extent the thermophysical properties of the two pure materials influence or determine the proper-ties of its corresponding alloy. It is to proof if data for pure materials can be used to predict the thermophysical properties of simple alloys. For this specific copper-silver alloy, there is a certain mutual solid solubility with a quite large miscibility gap. Ag-28Cu is not a single phase alloy but an eutectic alloy with two phases. (c) 2005 Elsevier B.V. All rights reserved.