الفهرس 
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Abstract
Owing to the realization of the harmful influence of lead and lead containing alloys on the environment and human health, many Pb-free solder-alloys have been developed to replace Sn-Pb solders in electronic applications. The European community, US Environmental Protection Agency (EPA), and electronics industries have started initiatives to reduce lead usage. Many lead-free solders have been studied as replacements for Sn–Pb solders. Recently, tin-antimony alloys among white bearing metals (which may be either tin-base or lead free) have received amount of attention because of their high specific gravity, higher microstructure stability and higher melting point and also the most attractive candidate for surface mount technologies, as it provides better mechanical properties than do eutectic Sn–Pb solders.
In the present work, characterizations of the microstructure and mechanical properties were conducted on three lead-free solder alloys with the compositions (wt. %) of Sn–5Sb, Sn–5Sb–0.7Ag and Sn–5Sb–0.7Cu. The lead-free solders were prepared from Sn, Sb, Ag and Cu (Purity 99.97 %) as raw materials. A separate addition of the same amount of Ag and Cu are added with the near-peritetic Sn–5%Sb solder alloy to investigate the effect of a third element addition on the microstructural and mechanical properties of the newly developed ternary solder alloys. The microstructure was examined by optical microscopy (OM), scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDS) after etching. Phase identification of the alloy samples was carried out by X-ray diffractometry (XRD). The basic features of thermal properties of the three solder alloys have been studied by using the differential scanning calorimetry (DSC). Tensile stress-strain and creep tests were performed at constant temperatures 25, 70 and 120 oC after waiting time of 5 min for the test temperatures to determine the effect of Ag and Cu contents on the mechanical properties of mixed alloy.
X-ray diffraction analysis was performed to determine the phase composition of inter metallic compounds (IMCs) particles in the three as-cast Sn–5%Sb, Sn–5%Sb–0.7%Ag and Sn–5%Sb–0.7%Cu alloys. In general, all the as-cast experimental alloys are mainly composed of β-Sn phase and precipitated SbSn phase. However, the alloys containing Ag and Cu exhibited additional IMCs such as; Ag3Sn for Ag-containing solder and Cu6Sn5 for Cu-containing solder. Microstructural analysis revealed that both.