Thermodynamic calculations and characterization of the Bi–Ga–In ternary alloys

Manasijević, Dragan; Minić, Duško; Premović, Milena; Balanović, Ljubiša; Živkovič, Dragana; Manasijević, Ivana; Mladenović, Srba

doi:10.1016/j.jallcom.2015.12.233

Cited by 8 publications

(1 citation statement)

References 14 publications

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“…As shown in the 80 °C isothermal section of the Sn-Bi-In ternary system (Figure 7d), the ternary Sn-Bi-In liquid with the composition of Sn-54.0 wt.%Bi-25.6 wt.% In is in equilibrium with both (Bi) and (Sn) phases. Since the addition of Ga would further reduce the liquidus temperature [30], it is evident that the quaternary Sn-Bi-In-Ga liquid phase presented at 80 °C and solidified into BiIn IMC after ageing. As shown in the Ga- and Sn-mapping in Figure 7c, it is likely the BiIn IMC nucleated on the (Bi) phase and the final liquid phase enriched in Ga and Sn finally solidified near the (Sn) phase.…”

Section: Resultsmentioning

confidence: 99%

A Computational Thermodynamics-Assisted Development of Sn-Bi-In-Ga Quaternary Alloys as Low-Temperature Pb-Free Solders

et al. 2019

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Low-temperature lead (Pb)-free solders are demanding in the electronic packaging industry, because it would open the door for various economic choices of polymeric materials as substrates and also revives the lower cost processes. Here, we proposed a tin–bismuth–indium–gallium (Sn-52.5Bi-2.68In-1Ga, SBIG (in wt.%)) quaternary low-temperature solder, designed based on systematic CALPHAD (CALculation of PHAse Diagram)-type thermodynamic calculations and corresponding key experiments. The solidification behavior of SBIG was carefully elaborated based on the computations using the lever rule and the Scheil model, and the experiments in terms of thermal analyses and microstructures of sample produced with step-quenching and various cooling rates. The mechanical properties of as-cast and 80 °C-annealed SBIG as well as their microstructures and fracture surfaces were evaluated in the tensile tests. The proposed SBIG solder is with a low liquidus temperature of 141.9 °C and is typically composed of the primary (Sn) phase, the (Sn) + (Bi) eutectic structure and a small amount of (Ga) phase. Air cooling has been identified as a satisfactory cooling rate, which would not lead to the formation of the brittle BiIn intermetallic compound. The as-cast SBIG solder exhibited high yield strength (YS) of 43.7 MPa, high ultimate tensile strength (UTS) of 53.3 MPa and an extremely large elongation of 97.3% as comparing to the conventional eutectic Sn-58Bi solder (YS: 43.1 MPa, UTS: 49.5 MPa, and elongation: 37.5%). However, the proposed SBIG solder does not possess qualified thermal stability, that significant degradation in both strength and elongation were observed after being subjected to extensive thermal ageing at 80 °C for 504 h.

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Section: Resultsmentioning

confidence: 99%