Properties of silver-tin alloys obtained from pyrophosphate-cyanide electrolytes containing EDTA salts

Abstract

Silver-tin alloy coatings are electrodeposited from a newly developed EDTA containing cyanide-pyrophosphate electrolyte and some properties of the obtained coatings, such as microhardness, internal stress, abrasion resistance, plug-in forces and electrical contact resistance depending upon the applied current density or the tin content of the alloy, respectively, are investigated. The codeposition of tin leads to the change of the tensile stress of pure silver coatings to compressive stress in the formed solid solution of the alloy and to almost stress free coatings at high current densities. The microhardness runs over a maximum at current densities, where the silver lattice is saturated with tin and the deposition of phase heterogeneous coatings starts. The abrasion resistance diminishes at increased tin content, and the changes of the electrical contact resistance are in the opposite direction. The measured plug-in forces show the lubricating properties of the alloy coatings.

Corrosion Resistance of Multilayered Sn/Ag3Sn Films Electroplated on Cu Alloys for Highly Reliable Automotive Connectors

“…The multilayered Sn/Ag 3 Sn specimen consists of an Ag-Sn alloy layer with thickness of 50 nm, and a Sn layer and a Cu 6 Sn 5 layer similar to the Sn-RF specimen. It should be noted that the multilayered Sn/Ag 3 Sn film is different from conventional Sn-Ag alloy electroplating [19][20][21][22][23][24] and commercial Sn-Ag hot-dip coatings, 1,25 in which the Ag component (the former) or the Ag 3 Sn particles (the latter) are distributed the whole thickness of coatings. The multilayered Sn/Ag 3 Sn film in the present study was designed to utilize effectively the highly conductive Ag alloy film on the top layer and to minimize Ag usage by 1/40.…”

Enhanced destruction of Cu(CN)32− by H2O2 under alkaline conditions in the presence of EDTA/pyrophosphate

“…The effect of slurry pH on cyanide destruction varied depending upon the doses of copper. Though Beattie and Polyblank [21] It is known that, besides cyanide, EDTA and pyrophosphate are also used in electroplating solutions [22,23]. Generally, cyanide, pyrophosphate and EDTA occurred simultaneously in the waste streams.…”

Properties of electrodeposited silver–cobalt coatings

“…9) and the abrasion resistance increases in the investigated range of the current density or cobalt content, in contradiction to the cases of alloy coatings of silver with other ''softer'' metals, like Bi, In, Sb, etc. [13].…”

“…This paper represents a further study on the properties of different silver alloy systems previously investigated [10][11][12][13].…”