Effect of nano-TiO2 addition on microstructural evolution of small solder joints

Effect of kaolin geopolymer ceramic addition on the properties of Sn-3.0Ag-0.5Cu solder joint

“…According to the theory of heterogenous nucleation, the presence of KGC particles in an alloy of SAC305 solder matrix acted as heterogeneous nucleation sites for β-Sn and eutectic phases. The β-Sn and eutectic phases nucleate on the surface of KGC particles in the means to reduce the thermodynamic barrier of nucleation as suggested by Li et.al [14].…”

“…This was due to the ceramic reinforcements were extremely stable at high temperature and no new excessive phase will form either during the fabrication or due to the large temperature difference between the reinforcing particles and solder alloys [2,6]. Reinforcing the solder matrix with small amounts of ceramic particles including cerium oxide (CeO2) [9,10], zirconia (ZrO2) [11,12], titanium oxide (TiO2) [2,[13][14][15][16][17][18], silicon carbide (SiC) [19,20], silicon nitride (Si3N4) [21,22], iron oxide (Fe2O3) [23], strontium titanate (SrTiO3) [24], titanium carbide (TiC) [25], silicon dioxide (SiO2) [26], lanthanum oxide (La2O3) [27] and aluminium oxide (Al2O3) [28,29] have shown to improve microstructure formations, mechanical and thermal properties of solder. Li et al [9] hypothesized that the incorporation of ceramic particles in solder matrix may act as heterogenous nucleation sites for β-Sn and eutectic phase which could increase the nucleation rate and may result in smaller grain size.…”