Phase transformations and thermal conductivity of the In-Ag alloys

Dragan Miroslav Manasijevic,Dusko Minic,Ivana Markovic,Ljubiša Balanović,Milan Gorgievski,Milena Premovic,Nada Strbac,Uros Stamenkovic

doi:10.30544/488

Abstract

Phase transformations and thermal conductivity of three In-Ag alloys with 5, 15, and 45 wt.% of Ag were experimentally investigated in the present work. Phase transition temperatures were measured using differential scanning calorimetry (DSC). DSC heating scans were compared with the equilibrium and non-equilibrium solidification paths, calculated by using optimized thermodynamic parameters from literature and calculation of phase diagrams (CALPHAD) method. The flash method was employed for the determination of thermal diffusivity and thermal conductivity of the investigated alloys in the temperature range from 25 to 100 °C. It has been found that an increase in silver content does not lead to an increase in the thermal conductivity of the investigated alloys. Thermal conductivities for all three investigated In-Ag alloys slightly decrease with temperature increasing.

Highlights

Indium is a low-melting, highly malleable and ductile metal
Equilibrium solidification path corresponds to the phase diagram of the Ag-In system i.e. to the conditions of very slow cooling/heating of the alloy
The interpretation and analysis of differential scanning calorimetry (DSC) heating scans were performed with the assistance of equilibrium and non-equilibrium solidification paths computed from thermodynamic data

Summary

Introduction

Indium is a low-melting, highly malleable and ductile metal. It is often used as a strengthening agent in lead-based solder and as a base material in low-meltingtemperature solders [1]. Conducted investigations include the determination of phase transition temperatures using the DSC method and thermal conductivity measurements using the xenon-flash technique. Investigation of melting behavior Experimentally obtained results were compared with the calculated equilibrium and non-equilibrium Scheil solidification paths using the optimized thermodynamic parameters from the COST 531 lead-free solder database [4] and PANDAT software [7].

Results

Conclusion