Benoil will use any foil appropriate to an application. We initially
offered nickel which is, however, not always suitable. Alloy 600
(Inconel 600 - TM Inco) is much more resistant to sour gas (hydrogen sulphide)
atmosphere. Even it is not perfectly resistant; plated forms are one
approach for extreme conditions or cocktail mixtures. In some conditions,
316 stainless steel is appropriate. We now offer also the more highly
corrosion resistant Alloy C-276 (Hastelloy C-276 - TM Haynes); this is
considered better than the plating concept as the alloy is coherent,
while plating can crack as the disc expands near its rupture point.
Other materials will be considered and Monel 400 (TM Inco) has been added
recently. We have also used copper, aluminium, Kovar and titanium, but in
special designs, as these do not readily weld to stainless steel bodies.