Interconnection of thermal parameters, microstructure and mechanical properties in directionally solidified Sn-Sb lead-free solder alloys

Author(s)

Dias, Marcelino ^[1] ; Costa, Thiago ^[1] ; Rocha, Otavio ^[2] ; Spinelli, Jose E. ^[3] ; Cheung, Noe ^[1] ; Garcia, Amauri ^[1]

Affiliation

^[1] Univ Campinas UNICAMP, Dept Mfg & Mat Engn, BR-13083860 Campinas, SP - Brazil

^[2] Fed Inst Educ Sci & Technol IFPA, BR-66093020 Belem, PA - Brazil

^[3] Fed Univ Sao Carlos UFSCar, Dept Mat Engn, BR-13565905 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: MATERIALS CHARACTERIZATION; v. 106, p. 52-61, AUG 2015.
• Web of Science Citations: 12

Abstract

Considerable effort is being made to develop lead-free solders for assembling in environmental-conscious electronics, due to the inherent toxicity of Pb. The search for substitute alloys of Pb-Sn solders has increased in order to comply with different soldering purposes. The solder must not only meet the expected levels of electrical performance but may also have appropriate mechanical strength, with the absence of cracks in the solder joints. The Sn-Sb alloy system has a range of compositions that can be potentially included in the class of high temperature solders. This study aims to establish interrelations of solidification thermal parameters, microstructure and mechanical properties of Sn-Sb alloys (2 wt.%Sb and 5.5 wt.%Sb) samples, which were directionally solidified under cooling rates similar to those of reflow procedures in industrial practice. A complete high-cooling rate cellular growth is shown to be associated with the Sn-2.0 wt.%Sb alloy and a reverse dendrite-to-cell transition is observed for the Sn-5.5 wt.%Sb alloy. Strength and ductility of the Sn-2.0 wt%Sb alloy are shown not to be affected by the cellular spacing. On the other hand, a considerable variation in these properties is associated with the cellular region of the Sn-5.5 wt.%Sb alloy casting. (C) 2015 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 13/23396-7 - Effects of solidification MicrostructureParameters of Aluminum-based multicomponent alloys (Al-Mg-Si; Al-Sn-Cu; Al-Zn-Mg) on the resistances to Corrosionand tribocorrosion degradation
• Grantee: Amauri Garcia
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/09267-0 - Microstructural evolution in the transient solidification of monophasic and peritectic Sn-Sb solder alloys (and Sn-Sb-X) and in solder/substrate interfacial layers
• Grantee: José Marcelino da Silva Dias Filho
• Support Opportunities: Scholarships in Brazil - Doctorate