, Volume 21, Issue 5, pp 595-598,
Open Access This content is freely available online to anyone, anywhere at any time.
Date: 01 Feb 2012

Wetting of Sn-Zn-xIn (x = 0.5, 1.0, 1.5 wt%) Alloys on Cu and Ni Substrates

Abstract

Wetting angles of Sn-8.8Zn and Sn-8.8Zn-xIn alloys (x = 0.5, 1.0, 1.5 wt%) were studied with the sessile drop method. Wetting tests were carried out for 900 s in the presence of ORM0 flux at 493, 523, and 573 K on copper and at 523 K on nickel substrates, respectively. It was found that the addition of In to Sn-8.8Zn alloy improves its wetting on both substrates by reducing the value of apparent wetting angle. Also, with increasing temperature a decrease of wetting angle on copper is observed in the case of 0 and 1.5 wt% of In alloys. Solidified solder-substrate couples were cross-sectioned and examined with scanning electron microscopy coupled with electron dispersive X-ray analysis. Interlayers were found at the interface of solders with copper and nickel, and their compositions are close to Cu5Zn8 and Ni5Zn21 intermetallics, respectively. However, in the case of Sn-8.8Zn-1.5/Ni couple small scallops are observed instead of continuous interlayer.

This article is an invited submission to JMEP selected from presentations at the Symposia “Wetting, soldering and brazing” and “Diffusion bonding and characterization” belonging to the Topic “Joining” at the European Congress and Exhibition on Advanced Materials and Processes (EUROMAT 2011), held September 12-15, 2011, in Montpellier, France, and has been expanded from the original presentation.