(1. 沈陽工業(yè)大學 材料科學與工程學院,沈陽 110023;
2. 北京航空材料研究院,北京 100095)
摘 要: 通過蠕變曲線測定及組織形貌觀察,研究固溶及淬火工藝對FGH95鎳基合金蠕變行為及變形特征的影響。結(jié)果表明:固溶后經(jīng)油浴冷卻的合金的組織結(jié)構(gòu)由不均勻的顆粒及γ′相組成,粗大γ′相在邊界區(qū)域呈不連續(xù)分布,邊界區(qū)域為γ′相貧化區(qū);經(jīng)鹽浴熱處理后合金中無粗大γ′相,晶粒略微長大,晶內(nèi)細小的γ′相彌散分布,粒狀(Ni,Ti)C相沿晶界不連續(xù)析出;在650 ℃和1 034 MPa條件下,經(jīng)鹽浴熱處理后合金的蠕變壽命較長,測定出該合金的蠕變激活能為542.07 kJ/mol;固溶后經(jīng)油浴冷卻的合金在蠕變期間的變形機制是位錯發(fā)生雙取向滑移,而固溶后經(jīng)鹽浴冷卻合金在蠕變期間可形成位錯纏結(jié)和層錯等位錯組態(tài),晶界及晶界處不連續(xù)析出的粒狀碳化物可有效阻礙位錯滑移,這是合金具有較高蠕變抗力和較長蠕變壽命的主要原因。
關(guān)鍵字: 高溫合金;粉末鎳基合金;FGH95鎳基合金;熱處理;組織結(jié)構(gòu);蠕變性能
(1. School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110023, China;
2. Beijing Institute of Aeronautical Materials, Beijing 100095, China)
Abstract:The effects of the solution and quenching technics on the microstructure and creep properties of FGH95 nickel-based superalloy were investigated by measurement of creep properties and microstructure observation. The results show that the microstructure of the solution treated alloy cooled by oil bath consists of the inhomogeneous particles and γ′ phase, the relatively thick γ′ phase discontinuously distributes in the boundary region that is poor of fine γ′ phase. No coarse γ′ phase is detected in the molten salt cooled alloy in which the grain size increases slightly and the fine γ′ phase dispersively distributes within the grains, and some of the particle-like (Ni, Ti)C phases precipitate discontinuously along the boundaries. Under the conditions of the applied stress of 1 034 MPa and 650 ℃, the molten salt cooled alloy displays a longer creep lifetime, and the creep activation energy of the alloy is measured to be 542.07 kJ/mol. During the creep, the deformed mechanism of the solution treated alloy cooled in oil bath is that the double orientation slipping of the dislocations is activated, the configuration of the dislocation tangles and stacking fault may be formed in the molten salt cooled alloy. Thereinto, the fact that the particles-like carbides are discontinuously precipitated along the boundary may effectively restrain the dislocation slipping, which is the main reason why this alloy possesses relatively good creep resistance and long creep lifetime.
Key words: high-temperature alloy; P/M nickel-based superalloy; FGH95 superalloy; heat treatment; microstructure; creep properties


