S.Q. Zhao
,
Y. Jiang
,
J.X. Dong
,
null
,
null
,
null
金属学报(英文版)
A novel nickel-based superalloy INCONEL 740 was under development for application in ultra-supercritical superheater tubers above 750℃. The precipitation behaviors of ?浊 phase and ?酌' particles of the alloy were investigated through experimental study and phase computation. Experimental results showed that ?浊 phase formed a Widmanst?覿tten pattern structure following long-term exposure at elevated temperatures and that the coarsening of ?酌' particle follows a cube rate law: 3 ∝ t. Thermodynamic calculation results showed that Al and Ti had an important effect on the precipitation behavior of ?酌' and ?浊 phases. Two suggested novel modified alloys, wherein the Al and Ti contents were modified, were designed and melted for the experimental study. The preliminary results indicated that the modified alloys exhibited higher structural stability following long-term exposure at 750℃ till 5000h.
关键词:
superalloy
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null
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null
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null
F.J. Liu
,
M.C. Zhang
,
J.X. Dong
,
Y.W. Zhang
金属学报(英文版)
High temperature oxidation behaviors of FGH96 P / M superalloy have been studied in air at temperatures ranging from 600 to 1000℃. By means of isothermal oxidation testing, X-ray
diffraction, SEM (scanning electron microscopy) and EDS (energy dispersive X-ray spectroscopy) analyses, the oxidation kinetics as well as the composition and morphology of scales were investigated. Thermodynamic calculations were used to explain the oxidation mechanism. The results showed that as the oxidation temperature increased, the oxidation rate, the scale thickness and scale spallation increased. FGH96 P / M superalloy exhibits good oxidation resistance at temperature below 800℃. The oxidation kinetics follows an approximately parabolic rate law, and the
oxide layer was mainly composed of Cr2O3, TiO2, and a little amount of NiCr2O4. The oxidation is controlled by the transmission
of chromium, titanium, and oxygen through the oxide scale.
关键词:
FGH96 P/M superalloy
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null
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null
