N 3677 (OTTO) Nickel powder, <150 μm, 99.99% Cas 7440-02-0 - used as catalysts for hydrogenation reactions. N 3677 (OTTO) Nickel powder, <150 μm, 99.99% Cas 7440-02-0 - used to create stainless steel and heat-resisting steel and provide some great anti-corrosion capabilities.