Silver brazing alloys of the American Welding
Society’s specification are best suited as filler
materials for joining ferrous and non-ferrous
metals and alloys[1,2]. Out of these alloys,
BAg-1 containing 42-44 per cent Ag, 15-17
per cent Cu, 18-22 per cent Zn and 20-22 per
cent Cd is an alloy for general purpose appli-
cations and widely used for brazing steel,
copper, brass, gun metal, tin bronze, alumini-
um and manganese bronzes, silver-based
contacts, nickel-based alloys and nickel silver
of all types[3,4]. This alloy has free flowing
characteristics and a narrow melting range. It
is essentially an alloy for use where joints are
closely fitted or where it is desired to employ a
single brazing alloy that will be effective in a
wide range of applications.
The alloy BAg-3 containing 45-51 per cent
Ag, 14.5-16.5 per cent Cu, 13.5-17.5 per cent
Zn, 15-17 per cent Cd and 2.5-3.5 per cent
Ni is also an alloy of wide wetting range and
particularly suitable for brazing carbide tool
tips to tool shanks and stainless steel[2-4].
Corrosion problems of these alloys are
encountered during use in different environ-
ments. However, corrosion data of these
alloys are rare in the literature. A detailed
experimental programme was undertaken at
the National Metallurgical Laboratory to
study the corrosion behaviour of these alloys
in various environments such as sulphide,
chloride, etc. with particular emphasis on
industrial and marine atmospheres.
Materials and experimental procedure
The alloys were air-melted, cast and
processed by rolling to a thickness suitable for
corrosion study. Standard sized test speci-
mens from these alloys were prepared for
immersion, electrochemical and environmen-
tal studies. Test specimens were polished up
to 600 grit emery paper, washed, rinsed, dried
and kept in a desiccator. These were then
degreased with acetone before use for tests.
For atmospheric exposure tests, standard
sized mirror finished test specimens were
exposed at an angle of 45° in the industrial
(Jamshedpur) as well as in the marine atmos-
phere (Digha, Bay of Bengal Seashore). The
corrosion rates of the above sample were
260
Anti-Corrosion Methods and Materials
Volume 44 · Number 4 · 1997 · pp. 260–264
MCB University Press · ISSN 0003-5599
S.C. Dev
Inder Singh
D.K. Basu
A.K. Bhattamishra and
C.S. Sivaramakrishnan
The authors
S.C. Dev, Inder Singh, D.K. Basu, A.K. Bhattamishra
and C.S. Sivaramakrishnanare all at the National
Metallurgical Laboratory, Jamshedpur, India.
Abstract
Corrosion data of the widely used silver brazing alloys
(BAg-1 and BAg-3) of the American Welding Society’s
(AWS) specification are scant in literature. Deals with the
study of the corrosion behaviour of these alloys in different
environments with particular emphasis on the industrial
and marine atmospheres.
Corrosion behaviour of
silver brazing alloys in
different environments
Contributed papers
The authors wish to record their thanks to the
Director of the National Metallurgical Laboratory,
Jamshedpur for his kind permission to publish this
paper.