A specific composition range and process sequence are described for the production of single crystal superalloy articles which have an exceptional combination of high temperature mechanical properties and resistance to oxidation and hot corrosion. The nominal composition is 6% Ta, 9% Cr, 5% Co, 1% Ti, 1% Mo, 7% W, 5.5% Al, 0.15% Hf balance essentially nickel. Material of this composition is cast and solidifed in single crystal form and heat treated to produce an optimum microstructure.