The microstructure change of sputtered Ni-3Cr-10Al nanocrystalline coating during oxidation in air at 900°C was observed and its eNct on oxide formation on the sputtered coating was studied. Twe results indicated...The microstructure change of sputtered Ni-3Cr-10Al nanocrystalline coating during oxidation in air at 900°C was observed and its eNct on oxide formation on the sputtered coating was studied. Twe results indicated that Ni3Al was segmpated during oxidation, on which Nio could be easily formcd. NiO could react with the trunsient γ-Al2O3 to form NiAl2O4 through solid reaction, whtch can be found on the oxide scale afer 200h oxidation. Thewtre, the oxide scale formed on sputtered Ni-3Cr10Al coating was not composed of a unltary layer of Al2 O3. Thc Al2O3 and NiAl2 O4 complex oxide scale bonded properly with substrate and showed gpod adhesion and good oxidation resistance.展开更多
The oxide formation on the sputtered Ni 3Cr 10Al nanocrystalline coating at 900 ℃ and 1 000 ℃ in air has been studied. The results indicated that an oxide scale composed of NiAl 2O 4 and Al 2O 3 was formed on the sp...The oxide formation on the sputtered Ni 3Cr 10Al nanocrystalline coating at 900 ℃ and 1 000 ℃ in air has been studied. The results indicated that an oxide scale composed of NiAl 2O 4 and Al 2O 3 was formed on the sputtered Ni 3Cr 10Al nanocrystalline coating whereas a unitary Al 2O 3 scale was not formed even when the Al content was high in the sputtered coating. The formation of NiAl 2O 4 was directly related to the precipitation of Ni 3Al in the coating during oxidation process. It was suggested that the precipitation of Ni 3Al contributed to the formation of NiO and therefore NiO could react with Al 2O 3 and form NiAl 2O 4. With increasing oxidation temperature, the effect of Ni 3Al precipitation on the formation of NiAl 2O 4 decreased.展开更多
The oxidation behavior of sputtered Ni-3Cr-20Al coating at 900℃ in air was investigated. A dense Al2O3 layer was formed on the sputtered Ni-3Cr-20AI coating after 200 h oxidation. However, owing to the segregation of...The oxidation behavior of sputtered Ni-3Cr-20Al coating at 900℃ in air was investigated. A dense Al2O3 layer was formed on the sputtered Ni-3Cr-20AI coating after 200 h oxidation. However, owing to the segregation of Ni3Al during oxidation process at high temperature, the spinel NiAI2O4 was also formed in the Al2O3 layer. It was found that the formation of NiAI204 had no detrimental effect on the oxidation resistance of the sputtered N?3O-20AI coating due to the excellent adhesion shown by the Al2O3 and NiAl2O4complex oxide scale.展开更多
文摘The microstructure change of sputtered Ni-3Cr-10Al nanocrystalline coating during oxidation in air at 900°C was observed and its eNct on oxide formation on the sputtered coating was studied. Twe results indicated that Ni3Al was segmpated during oxidation, on which Nio could be easily formcd. NiO could react with the trunsient γ-Al2O3 to form NiAl2O4 through solid reaction, whtch can be found on the oxide scale afer 200h oxidation. Thewtre, the oxide scale formed on sputtered Ni-3Cr10Al coating was not composed of a unltary layer of Al2 O3. Thc Al2O3 and NiAl2 O4 complex oxide scale bonded properly with substrate and showed gpod adhesion and good oxidation resistance.
文摘The oxide formation on the sputtered Ni 3Cr 10Al nanocrystalline coating at 900 ℃ and 1 000 ℃ in air has been studied. The results indicated that an oxide scale composed of NiAl 2O 4 and Al 2O 3 was formed on the sputtered Ni 3Cr 10Al nanocrystalline coating whereas a unitary Al 2O 3 scale was not formed even when the Al content was high in the sputtered coating. The formation of NiAl 2O 4 was directly related to the precipitation of Ni 3Al in the coating during oxidation process. It was suggested that the precipitation of Ni 3Al contributed to the formation of NiO and therefore NiO could react with Al 2O 3 and form NiAl 2O 4. With increasing oxidation temperature, the effect of Ni 3Al precipitation on the formation of NiAl 2O 4 decreased.
基金National Natural Science Foundation of China !under grant 59671060
文摘The oxidation behavior of sputtered Ni-3Cr-20Al coating at 900℃ in air was investigated. A dense Al2O3 layer was formed on the sputtered Ni-3Cr-20AI coating after 200 h oxidation. However, owing to the segregation of Ni3Al during oxidation process at high temperature, the spinel NiAI2O4 was also formed in the Al2O3 layer. It was found that the formation of NiAI204 had no detrimental effect on the oxidation resistance of the sputtered N?3O-20AI coating due to the excellent adhesion shown by the Al2O3 and NiAl2O4complex oxide scale.
