Low Temperature Soldering 6061 Aluminum Alloys by Using the Synthesized Sn9Zn Nano-Amorphous Particles

To meet the growing demand of technologies of high performance electronics, nano-solders have been widely developed. In the present study, Sn-Zn nano-amorphous particles with core–shell structure were synthesized by a chemical reduction method with NaBH4 as reduction agent and Polyvinylpyrrolidone (PVP) as a stabilizer. The size distribution and thermal behaviour of the as-synthesized nano-particles were controlled by the amount of PVP, whose concentration ranged from 3 to 30 wt%. And the change was comparatively confirmed by TEM, DSC and XRD analysis. The results revealed that PVP concentrations can not only regulate and control the size distribution of the nano-particles and the melting point, which could also change the ratio of amorphous shell to crystalline core in nanostructures. In addition, sintering behavior of this nano-solder soldering 6061 aluminum alloys and its corresponding mechanical properties were evaluated based on SEM, XRD and the shear tests. The results turned out the best bonding quality was obtained under the condition of the content of PVP is 10 wt%. The obtained shear strength was as high as 17.6 MPa, and the elemental composition of the thinner IMC layer was Al 2 Zn 3 , which revealed a good solderability property. The above analysis provided a new insight into the effects of PVP content on the interfacial reaction mechanism. This bonding technology was suitable for the electronic devices bonded at low temperature. Graphical Abstract