Properties and microstructure of Sn–0.7Cu–0.05Ni lead-free solders with rare earth Nd addition

The effects of rare earth Nd on the melting behavior, wettability, microstructure and mechanical properties of Sn–0.7Cu–0.05Ni solders have been investigated in this paper. The melting temperature was found to be slightly influenced with rare earth Nd addition. Results of wetting balance tests showe...

Full description

Saved in:
Bibliographic Details
Published in:Journal of materials science. Materials in electronics 2019-01, Vol.30 (2), p.1400-1410
Main Authors: Liu, Shuang, Xue, Song-bai, Zhong, Su-juan, Pei, Ying-ying, Sun, Hua-wei
Format: Article
Language:English
Subjects:
Characterization and Evaluation of Materials
Chemistry and Materials Science
Copper
Lead free
Materials Science
Mechanical properties
Melt temperature
Microstructure
Morphology
Nickel
Nucleation
Optical and Electronic Materials
Rare earth elements
Shear strength
Soldering
Solders
Solidification
Tin
Wettability
Wetting
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The effects of rare earth Nd on the melting behavior, wettability, microstructure and mechanical properties of Sn–0.7Cu–0.05Ni solders have been investigated in this paper. The melting temperature was found to be slightly influenced with rare earth Nd addition. Results of wetting balance tests showed that adding a proper amount of Nd could substantially improve the wettability of Sn–Cu–Ni solders by decreasing the wetting time and increasing the wetting force. The morphology evolution of solder matrix indicated that Nd contributed to the refinement and uniformity of the microstructure when added within an appropriate range. It was because the fine NdSn 3 particles formed primarily in the soldering process would act as heterogeneous nucleation sites during solidification. However, excessive addition of Nd was inadvisable due to the formation of large amounts of brittle and hard NdSn 3 compounds with bulk shapes. Meanwhile, moderate amount of rare earth Nd could inhibit the growth of interfacial (Cu,Ni) 6 Sn 5 IMCs during soldering. Results of micro-joints strength test also discovered that Sn–Cu–Ni–Nd soldered joints possessed sounder shear strength, which resulted from the refined microstructure and the improved solders/Cu interfacial morphology. These above results evaluated that the optimum content of Nd added into Sn–0.7Cu–0.05Ni solders was about 0.06 wt%.
ISSN:0957-4522
1573-482X
DOI:10.1007/s10854-018-0410-5