Coating system with NiCoCrAlY double-protection coat with varying chromium content and alloy

摘要

Layer system (1) comprises at least one substrate (4) with two layers (7), preferably an upper nickel-cobalt-chromium-aluminum-yttrium containing layer (A) (13) and lower nickel-cobalt-chromium-aluminum-yttrium containing layer (B) (10), where an amount of chromium in the upper layer (B) is at least 3 wt.%, preferably at least 5 wt.% less than the amount of chromium in the lower layer (A). An independent claim is also included for an alloy comprising 22-26 wt.%, preferably 23-25 wt.% cobalt, 23-25 wt.%, preferably 24 wt.% chromium, 10.5-12 wt.%, preferably 10.5 wt.% aluminum, 0.2-0.6 wt.%, preferably 0.3-0.5 wt.% yttrium, and nickel.