Strength of MWCNT-Reinforced 70Sn-30Bi Solder Alloys

Abstract

In this study, the effect of Cu-coated multi-walled carbon nanotubes (MWCNTs) on the tensile strength of 70Sn-30Bi solder alloy has been investigated. Copper was first deposited onto metal-activated MWCNTs by an electroless process and confirmed with a scanning electron microscope and energy dispersive spectroscopy. Sn-Bi alloy solder was reinforced with Cucoated MWCNTs with additions of 0.5 wt.%, 1 wt.%, 2 wt.%, and 3 wt.%, respectively. 70Sn-30Bi solder was produced by melting pure tin and bismuth in an inert gas atmosphere. Cu-coated MWCNTs were then added into the metal matrix by cold rolling, followed by hot pressing to disperse the carbon nanotubes (CNTs) in the matrix. Tensile tests were conducted on an mechanical testing and simulation (MTS) tester. The tensile strength was found to be proportional to the addition of Cu/MWCNTs, and about 47.6% increase in tensile strength over the pure alloy has been obtained for an addition of 3 wt.% Cu/MWCNTs. The Cu coating may enhance CNT dispersion to prevent tangling.

Research Status of Evolution of Microstructure and Properties of Sn-Based Lead-Free Composite Solder Alloys

“…Additionally, they also demonstrated that the doping of Ag-MWCNTs was effective to suppress the growth of IMC thickness of Sn-58Bi solder joint [35]. Similar phenomenon was also observed in the Sn-58Bi solder with the incorporation of Ni-coated CNTs [103] and Cu-coated CNTs [104]. Ma and Wu [105] reported that the thickness of total IMC layers decreased by 56.31% compared with the plain Sn5-8Bi-0.7Zn solder joint when the doping of GNSs was 0.114 wt%.…”

“…In recent years, with the appearance of CNTs and graphene, some investigations had been carried out to modify the Sn-Bi solders by the addition of CNTs and graphene [35, 36, 38, 61, 103-106, 108, 109]. Billah and Chen [104] researched the influence of Cu-coated MWCNTs on the mechanical properties of 70Sn-30Bi solder. It was found that the tensile strength of composite solder was proportional to the doping of MWCNTs, which increased by 47.6% when the addition of MWCNTs was 3 wt%.…”

Effect of Ce and Sb doping on microstructure and thermal/mechanical properties of Sn-1.0Ag-0.5Cu lead-free solder

“…The microstructure characteristics of solder alloys inevitably control their mechanical properties (El-Taher et al , 2021; Hammad and Ragab, 2019). The heterogeneous nucleation points increased with the Sb doping, which resulted in the diminution of grain size and the generation of more grain boundaries to hinder dislocation movement (Sun et al , 2016; Bakshi and Agarwal, 2011; Sharma et al , 2015; Billah and Chen, 2015). The strengthening mechanism conforms to the classical Hall–Petch relation (Armstrong, 2014).…”