Effect of temperature on the corrosion behavior of lead-free solders under polyvinyl chloride fire smoke atmosphere

The greatest advantage of Sn-Zn eutectic is its low melting point (198 oC) which is close to the melting point. of Sn-Pb eutectic solder (183 oC), as well as its low price per mass unit compared with Sn-Ag and Sn-Ag-Cu solders. In this paper, the effect of 0.0, 1.0, 2.0, 3.0, 4.0, and 5.0 wt. % Al as ternary additions on melting temperature, microstructure, microhardness and mechanical properties of the Sn-9Zn lead-free solders were investigated. It is shown that the alloying additions of Al at 4 wt. % to the Sn-Zn binary system lead to lower of the melting point to 195.72 ËšC.Â From x-ray diffraction analysis, an aluminium phase, designated Î±-Al is detected for 4 and 5 wt. % Al compositions. The formation of an aluminium phase causes a pronounced increase in the electrical resistivity and microhardness. The ternary Sn-9Zn-2 wt.%Al exhibits micro hardness superior to Sn-9Zn binary alloy. The better Vickers hardness and melting points of the ternary alloy is attributed to solid solution effect, grain size refinement and precipitation of Al and Zn in the Sn matrix.Â The Sn-9%Zn-4%Al alloy is a lead-free solder designed for possible drop-in replacement of Pb-Sn solders.Â Â

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Shear Strength and Dsc Analysis of High-Temperature Solders

Archives of Metallurgy and Materials ◽

10.2478/amm-2013-0031 ◽

2013 ◽

Vol 58 (2) ◽

pp. 529-533 ◽

Cited By ~ 5

Author(s):

R. Koleňák ◽

M. Martinkovič ◽

M. Koleňáková

Keyword(s):

Shear Strength ◽

High Temperature ◽

Lead Free ◽

Dsc Analysis ◽

Ultrasonic Activation ◽

Metallic Substrates ◽

Cu Substrate ◽

Lead Free Solders

The work is devoted to the study of shear strength of soldered joints fabricated by use of high-temperature solders of types Bi-11Ag, Au-20Sn, Sn-5Sb, Zn-4Al, Pb-5Sn, and Pb-10Sn. The shear strength was determined on metallic substrates made of Cu, Ni, and Ag. The strength of joints fabricated by use of flux and that of joints fabricated by use of ultrasonic activation without flux was compared. The obtained results have shown that in case of soldering by use of ultrasound (UT), higher shear strength of soldered joints was achieved with most solders. The highest shear strength by use of UT was achieved with an Au-20Sn joint fabricated on copper, namely up to 195 MPa. The lowest average values were achieved with Pb-based solders (Pb-5Sn and Pb-10Sn). The shear strength values of these solders used on Cu substrate varied from 24 to 27 MPa. DSC analysis was performed to determine the melting interval of lead-free solders.

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The technical, social, and legal outlook for lead-free solders

Proceedings of the 4th International Symposium on Electronic Materials and Packaging, 2002. ◽

10.1109/emap.2002.1188807 ◽

2003 ◽

Cited By ~ 7

Author(s):

P. Casey ◽

M. Pecht

Keyword(s):

Lead Free ◽

Lead Free Solders

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