Microstructure Characteristics and Thermodynamic Calculation ofPrecipitation Phases in a New Ni-Co-Based Superalloy
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摘要: 利用光学显微镜和扫描电镜观察新型Ni-Co基高温合金的铸态组织，采用JMatPro软件在平衡和非平衡凝固条件下对该合金进行热力学计算，研究了合金的相析出特点。结果表明：试验合金呈现枝晶形貌，偏析严重，主要组织为γ'相、η相、γ/γ'共晶组织以及MC碳化物。平衡凝固条件下，试验合金的主要析出相为γ'、η、μ、σ、碳化物以及硼化物；钛和铝含量增加导致γ'相析出量增加，析出温度升高；η相析出温度和析出量随钛含量增加呈线性增加。在非平衡凝固过程中，钛、钼元素富集在液相中，而铝、铬、钴和钨元素在液相中贫乏。
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关键词:
- 新型Ni-Co基高温合金 /
- 热力学计算 /
- 平衡析出相 /
- 析出温度
Abstract: The as-cast microstructure of a new Ni-Co-based superalloy was observed by optical microscopy and scanning electron microscopy. The thermodynamic calculation of the alloy was carried out by JMatPro software under equilibrium and non-equilibrium solidification conditions to study the phase precipitation characteristics. The results show that the test alloy exhibited dendritic morphology and severe segregation, and mainly consisted of γ' phase, η phase, γ/γ' eutectic structure and MC carbides. Under equilibrium solidification conditions, the main precipitation phases of the test alloy were γ', η, μ, σ, carbides and borides. Increasing Ti and Al content led to an increase in γ' phase precipitation amount and precipitation temperature. The precipitation temperature and amount of η phase increased linearly with increasing Ti content. In the non-equilibrium solidification process, Ti and Mo elements were enriched in the liquid phase, while Al, Cr, Co and W elements were poor in the liquid phase. -
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[1] CUI C Y, SATO A, GU Y F, et al.Phase stability and yield stress of Ni-base superalloys containing high Co and Ti[J].Metallurgical and Materials Transactions A, 2006, 37(11):3183-3190.
[2] GU Y, HARADA H, CUI C, et al.New Ni-Co-base disk superalloys with higher strength and creep resistance[J].Scripta Materialia, 2006, 55(9):815-818.
[3] CUI C Y, GU Y F, HARADA H, et al. Microstructures and tensile properties of new Ni-Co-base disk superalloys[C]//Proceedings of TMS Annual Meeting. Orlando:[s.n.], 2007:27-36.
[4] FUKUDA T, GU Y F, CUI C Y, et al. Effect of heat treatment conditions on microstructures of new Ni-Co based superalloys for turbine disks[J]. Journal of the Japan Institute of Metals, 2007, 71(9):667-671.
[5] CUI C Y, GU Y F, PING D H, et al. Phase constituents and compressive yield stress of Ni-Co base alloys[J]. Materials Transactions, 2008, 49(3):424-427.
[6] 郭建亭.高温合金材料学[M].北京:科学出版社, 2008. GUO J T.Materials science and engineering for superalloys[M].Beijing:Science Press, 2008.
[7] GU Y F, FUKUDA T, CUI C, et al.Comparison of mechanical properties of TMW alloys, new generation of cast-and-wrought superalloys for disk applications[J].Metallurgical and Materials Transactions A, 2009, 40(13):3047-3050.
[8] GU Y F, CUI C, PING D, et al.Creep behavior of new kinds of Ni-Co-base superalloys[J].Materials Science and Engineering:A, 2009, 510/511:250-255.
[9] 杜金辉, 吕旭东, 董建新, 等.国内变形高温合金研制进展[J].金属学报, 2019, 55(9):1115-1132. DU J H, LÜ X D, DONG J X, et al.Research progress of wrought superalloys in China[J].Acta Metallurgica Sinica, 2019, 55(9):1115-1132.
[10] YUAN Y, GU Y, ZHONG Z, et al.Controlling the deformation mechanism in disk superalloy at low and intermediate temperatures[C]//Superalloys 2012(Twelfth International Symposium).[S.l.]:John Wiley & Sons, Inc., 2012:35-42.
[11] OSADA T, GU Y F, NAGASHIMA N, et al.Optimum microstructure combination for maximizing tensile strength in a polycrystalline superalloy with a two-phase structure[J].Acta Materialia, 2013, 61(5):1820-1829.
[12] OSADA T, NAGASHIMA N, GU Y F, et al.Factors contributing to the strength of a polycrystalline nickel-cobalt base superalloy[J].Scripta Materialia, 2011, 64(9):892-895.
[13] XU L, CUI C Y, SUN X F.The effects of Co and Ti additions on microstructures and compressive strength of Udimet710[J].Materials Science and Engineering:A, 2011, 528(27):7851-7856.
[14] 孟凡国, 孔胜国, 李维, 等.K488合金平衡相的热力学计算[J].航空材料学报, 2018, 38(1):40-46. MENG F G, KONG S G, LI W, et al.Thermodynamic calculation of equilibrium phases of K488 alloy[J].Journal of Aeronautical Materials, 2018, 38(1):40-46.
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