Thermal Coefficients and Thermal Conductivities of Solid and Liquid Phases for Pure Ag, Pure Sn and Their Binary Alloys

Authors : Fatma Meydaneri, Buket Saatçi

Pages : 81-91

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Publication Date : 2010-01-15

Article Type : Research

Abstract :The variations of thermal conductivities of solid phases versus temperature for pure Sn and eutectic Sn-3.5 wt. % Ag, Sn- 1.5 wt. % Ag binary alloys were measured with a radial heat flow apparatus. The thermal conductivities of the solid phases at their melting temperature were also found to be 0.606 ± 0.06, 0.84 ± 0.09, 0.69 ± 0.07 W/K.cm. From the graphs of the solid phases thermal conductivity variations versus temperature, temperature coefficients for pure Sn, pure Ag and eutectic Sn- 3.5 wt. % Ag, Sn- 1.5 wt. % Ag binary alloys were found to be 0.00098, 0.00024, 0.00087, 0.0014 K-1, respectively. The thermal conductivity ratios of liquid phase to solid phase for the pure Sn and eutectic Sn-3.5 wt. % Ag binary alloy at their melting temperature were found to be 1.11 and 1.09 with a Bridgman type directional solidification apparatus. Thus the thermal conductivities of liquid phases for pure Sn and eutectic Sn-3.5 wt. % Ag binary alloy at their melting temperature were evaluated to be 0.67 and 0.92 W/K.cm, respectively by using the values of solid phase thermal conductivities, S and the thermal conductivity ratios of liquid phase to solid phase, R.
Keywords : Thermal Conductivity, Radial Heat Flow, Directional Solidification, Ag-Sn Alloy, Thermal Coefficient