Abstract: For use in the making of coins a laminated composite is proposed which can be used to substitute coins made of nickel and consists of a combination of a ferritic chromium steel and an austenitic nickel-chromium steel. In dependence of the nature of the existing system used to discriminate the nickel coins to be substituted, a laminated composite may be used which has a core layer consisting of the ferritic chromium steel and provided on both sides with a cladding having a thickness of 2 to 10% of the total thickness and consisting of the austenitic nickel-chromium steel, or a laminated composite which comprises a core layer consisting of the austenitic nickel-chromium steel and provided on both sides with a cladding having a thickness of 20 to 40% of the total thickness and consisting of the ferritic chromium steel. An optimum approxmation of the acceptability ranges adjusted for nickel in the discriminating systems can be achieved by a proper selection of the ratios of the thicknesses of the layers.

Abstract: For use in making components which are required to have a very high resistance to uniform corrosion and against pitting and crevice corrosion under very highly corrosive conditions encountered in up to date chemical process technology and environmental protection technology, for instance, in flue gas desulfurizing plants for concentrating sulfuric acid, and which are required to be manufactured satisfactorily by conventional hot and cold forming processes an alloy is employed which contains (in % by weight) 22.0 to 24.0 chromium, 15.0 to 16.5 molybdenum, up to 0.3% tungsten, up to 1.5% iron, up to 0.4% vanadium, 0.1 to 0.4% aluminum, 0.001 to 0.04% magnesium and 0.001 to 0.01 calcium, balance nickel and inevitable accompanying elements and impurities.

Abstract: Disclosed in an improvement in a known Ni-Cr-Fe alloy.The alloy of the invention contains 30 to 32% nickel; 26 to 28% chromium; 0.5 to 1.5% copper; 6 to 7% molybdenum; up to 2% manganese; up to 1.0% silicon; up to 0.2% aluminum; up to 0.03% carbon; 0.10 to 0.25% nitrogen; balance iron and usual impurities.The alloy of the invention has increased pitting corrosion potential and critical crevice corrosion and pitting corrosion temperatures whereas the resistance of the alloy to commercially pure phosphoric acid has not been decreased.