Evaluation of the microstructure, thermal, and mechanical characteristics of Sn-9Zn reinforced with Ni and ZrO2 nanoparticles via vacuum melting process

Abstract

The impact of minor additions of nickel and ZrO2 nanoparticles to eutectic Sn-9wt%Zn (SZ) prepared by vacuum melting technique was investigated. The morphologies and microstructures were carried out using an optical microscope (OM) and field emission scanning electron microscope technique (FESEM) escorted by energy dispersive x-ray spectrometry (EDX). The phase structure of the specimens was confirmed by an x-ray diffractometer (XRD). The results obtained demonstrate that small Ni addition causes a major grain refinement of β-Sn, due to the formation of the fine intermetallic compounds Ni5Zn21 and Sn3Ni4Zn3 phases and refines the formation of α- Zn lamellar phase. The melting temperature of the recently discovered solder alloys was lower than that of the eutectic Sn-Zn solders (∆Tm ∼ 28 °C) as a result of the preparation technique and the incorporation of Ni and ZrO2 nanoparticles. The tensile test showed enhanced the mechanical properties of SZ solder as a result of the addition of third elements. The experimental results showed that of all the alloys under investigation, the SZN903 alloy had the greatest UTS and YS values. The enhanced strength of the SZ-ZrO2 alloy defended the results of σ UTS and increased the stress exponent parameters, n, by ∼20%. All solders had an activation energy Q that measured between ∼35.62 kJ mol−1 to ∼58.12 kJ mol−1 which comparable to the pipe-diffusion mechanism.