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李梦贤，等：电子束精炼FGH4096高温合金的高温氧化行为

chromium in 1 atm oxygen at 950 ℃［J］. Oxidation of of Materials Science，1995，30（1）：201-211.

Metals，1987，28（1）：109-125. ［28］ LI Y，TAN Y，YOU X G，et al. Effect of trace impurity
［27］ LE GALL M，HUNTZ A M，LESAGE B，et al. Self- elements on the high-temperature oxidation resistance

diffusion in α-Al 2 O 3 and growth rate of alumina scales of a high-purity nickel-based superalloy［J］. Corrosion
formed by oxidation：Effect of Y 2 O 3 doping［J］. Journal Science，2023，211：110904.

High Temperature Oxidation Behavior of FGH4096 Superalloy Prepared by
Electron Beam Refining

LI Mengxian, LI Yi, TAN Yi, CHANG Kai, LI Pengting
(Key Laboratory for Energy Beam Metallurgy and Advanced Materials Preparation of Liaoning Province, School of Materials
Science and Engineering, Dalian University of Technology, Dalian 116024, China)

Abstract: The FGH4096 alloy with an oxygen impurity mass fraction of only 0.000 9% was prepared by
electron beam refining, and was subjected to constant temperature oxidation tests at 750 ℃ and 900 ℃ for 100 h. The
surface morphology, cross-section structure, and phase composition of the oxide film were investigated, and the high
temperature oxidization behavior of the alloy was analyzed and compared with that of the FGH4096 alloy with an oxygen
impurity mass fraction of 0.001 6% prepared by vacuum induction melting. The results show that compared with those
of the alloy prepared by vacuum induction melting, the increment of oxidizing mass per unit area and the thickness of
oxide film of the FGH4096 alloy prepared by electron beam refining after high temperature oxidation under the same
conditions were smaller, and the average oxidation rates at the oxidizing temperatures of 750, 900 ℃ were both less than
−2
−1
0.1 g · m · h ; the alloy was complete oxidation resistant. After oxidation at 900 ℃ for 100 h, the oxide film of the
alloy consisted of TiO 2 and Co(Ni)Cr 2 O 4 in the outermost layer, Cr 2 O 3 in the middle layer and Al 2 O 3 in the inner layer.
Compared with those of the alloy prepared by vacuum induction melting, the oxide film of the alloy prepared by electron
beam refining was thinner with less porous and better uniformity and densification, and the alloy had lighter degree of
internal oxidation. At the initial stage of oxidation, TiO 2 and Cr 2 O 3 were formed on the surface of the alloy. With the
extension of oxidation time, Co(Ni)O generated in the outer layer reacted with Cr 2 O 3 to form Co(Ni)Cr 2 O 4 spinel phase;
the oxide film was gradually dense, and a large amount of Al 2 O 3 was formed in the inner layer at low oxygen partial
pressure. The content of oxygen impurities in the alloy by electron beam refining was relatively low, the number of
defects was relatively few, which effectively reduced the growth rate of n-type semiconductor oxide Al 2 O 3 along the grain
boundaries, resulting in the relatively small oxide film thickness.
Key words: FGH4096 superalloy; electron beam refining; impurity element; oxidation resistance

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