A turbine engine apparatus includes a structural component made of a superalloy material. A protective coating is disposed on the structural component and has a composition that consists essentially of up to 30 wt % cobalt, 5-40 wt % chromium, 7.5-35 wt % aluminum, up to 6 wt % tantalum, up to 1.7 wt % molybdenum, up to 3 wt % rhenium, up to 5 wt % tungsten, up to 2 wt % yttrium, 0.05-2 wt % hafnium, 0.05-7 wt % silicon, 0.01-0.1 wt % zirconium, and a balance of nickel.