الفهرس 
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Abstract
The present study basically covers studying the effect of adding TiO2 nanoparticles on thermal, structural and mechanical properties of Sn-5wt% Sb-2wt% In (SSI52) solder alloy. Three topics are discussed:
1) Studying the effect of 0.22%TiO2 nanoparticles addition on thermal and microstructure characteristics of SSI52 ordinary solder.
2) Studying the effect of strain rate e\ and testing temperatures T on the stress-strain characteristics of SSI52 ordinary and SSI52 composite wire samples.
3) Studying indentation creep characteristics of the two solder alloys under effect of different aging temperature. The experimental results were examined under different loads.
In the first topic, Thermal analysis and microstructure evolutions of both the ordinary solder SSI52 and SSI52- 0.22 wt.% nano-sized TiO2 composite solder was discussed. Thermal properties of the selected solder alloys have been studied by using the differential scanning calorimetry (DSC) and the microstructure was examined by scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDS). Phase identification of the alloy samples was carried out by X- ray diffractometry (XRD). The results showed that the observed endothermic peaks of the SSI52 ordinary solder and SSI52 composite solder were found shifted from 238.46 to 238.99 oC. A touch small variation within the melting temperature (0.53 oC) after incorporating the TiO2 NP within the ordinary alloy. Microstructural analysis revealed that InSn and SbSn IMC particles and the P-Sn phase were detected in both SSI52 ordinary and SSI52 composite solders. Addition of 0.22 wt.% TiO2 nanoparticles yields uniform dispersion of these IMCs within the Sn-rich mixture producing a fine network like microstructure with the P-Sn.
In the second topic, stress-strain tests for SSI52 ordinary and SSI52 composite solder alloys were performed under the effect of different strain rates ranged from 1.3 x 10-3 to 1.6 x 10-2 s-1 at different testing temperatures T in the range of 298 to 373 K. The results showed that increasing strain rates or decreasing the testing temperatures and the existence of the nano-sized TiO2 particles resulted in increasing the work hardening parameter (WHP) ultimate tensile stress GUTS, yield stress
Gy and stress exponent (n). For ordinary and composite solders, the activation energy Q displays a permanent dependency on the addition of TiO2 nanoparticles and variability in strain rate. The average activation energy is " ~ "0.45 ev for SSI ordinary and " ~ "0.47 ev SSI composite LFS alloys, respectively.
In the third topic, microhardness investigation was performed using Vickers hardness tester at room temperature using loads of 0.098, 0.490, 0.980 and 1.96 N for dwell time ranging from 10 to 100 sec. The hardness of TiO2-contanined solder alloy at different loads was found to have higher values than those of ordinary solder. The creep behavior of ordinary and composite solders was studied using indentation measurements at different loads for samples thermally aged for 10 hours at 110 and 160 oC and compared with the as-cast samples. The variation in microhardness with dwell time in ordinary and composite solder alloys for the as-cast and aging, revealed that HV decreased by increasing the aging temperature which can be explained by the redistribution process of IMCs according to the surface energy property.