In this paper, a metallic protective coating is investigated as a diffusion barrier on the second generation single crystal superalloy DD6. A double layer of NiCoCrAlY/Ru coating is prepared by electroplating and electron beam physical vapor deposition (EB-PVD) on a sample of single crystal superalloy DD6. Also, a single NiCoCrAlY coating is deposited onto the single crystal superalloy by EB-PVD. The results show that an interdiffusion zone (IDZ) of ~55 μm and a secondary reaction zone (SRZ) of ~25 μm are formed in the superalloy after 300 h heat-treatment at 1 050 ℃ in atmospheric environment. Compared with the single NiCoCrAlY coating, the NiCoCrAlY/Ru coating effectively suppressed the formation of SRZ in the superalloy. There are only tiny amounts of topologically close-packed phases (TCP) precipitated in the superalloy.
WANG Juan, PENG Hui, CHEN Guozhong, GUO Hongbo, GONG Shengkai. Impact of Ru Buffer Layer on Diffusion Behavior Between NiCoCrAlY and Single Crystal Superalloy DD6[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2011, 32(4): 758-764. DOI: CNKI:11-1929/V.20101110.1442.001
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