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

Author:

Yang Chih-han,Zhou Shiqi,Lin Shih-kangORCID,Nishikawa Hiroshi

Abstract

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.

Funder

Ministry of Science and Technology, Taiwan

Publisher

MDPI AG

Subject

General Materials Science

Reference31 articles.

1. Interfacial reactions in the Sn–20 at.% In/Cu and Sn–20 at.% In/Ni couples at 160 °C

2. Lead-Free Electronic Solders;Chen,2006

3. Directive 2002/95/EC of the European parliament and of the council of 27 January 2003 on the restriction of the use of certain hazardous substances in electrical and electronic equipment;Off. J. Eur. Union,2003

4. Microstructure, elastic modulus and shear strength of alumina (Al2O3) nanoparticles-doped tin–silver–copper (Sn–Ag–Cu) solders on copper (Cu) and gold/nickel (Au/Ni)-plated Cu substrates

5. Wetting behaviour and reactivity of lead free Au–In–Sn and Bi–In–Sn alloys on copper substrates

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