Influence of Directional Solidification Process Parameters on Casting Structure of Third-generation Nickel-based Single-crystal Superalloys

ZHU Xiaolong; YU Zefeng; LI Ke; HUANG Xiaoming; CHEN Senhong; CHEN Haotian; WANG Xiaoshan; ZENG Long; XIA Mingxu; LI Jianguo

doi:10.3969/j.issn.1674-6457.2025.11.003

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Journal of Netshape Forming Engineering ›› 2025, Vol. 17 ›› Issue (11) : 37-46. DOI: 10.3969/j.issn.1674-6457.2025.11.003

Intelligent Processing of Advanced Materials

Influence of Directional Solidification Process Parameters on Casting Structure of Third-generation Nickel-based Single-crystal Superalloys

ZHU Xiaolong¹, YU Zefeng², LI Ke², HUANG Xiaoming², CHEN Senhong³, CHEN Haotian¹, WANG Xiaoshan¹, ZENG Long^3,*, XIA Mingxu¹, LI Jianguo³

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Abstract

The work aims to optimize the cast structure of the third-generation single-crystal superalloy by using argon gas protection and adjusting the withdraw rate. The third-generation nickel-based single-crystal superalloy single crystal test rods were prepared by HRS directional solidification and argon gas-protected HRS directional solidification at two pull rates, 40 μm/s and 80 μm/s, respectively. The microstructure of the alloy casting was observed by optical microscope and scanning electron microscope, and the influence of withdraw rate on the evolution of alloy structure was analyzed. In the directional solidification test of HRS and argon gas-protected HRS, the spacing, porosity, eutectic content and γ' phase size of the cast structure decreased with the increase of the withdraw rate. Segregation of Re, W, and Ta decreased, segregation of Al and Mo increased, while segregation of Cr and Co showed no significant change. When the argon gas-protected HRS was subject to directional solidification, the cast structure showed a decreasing trend except for the γ' phase size at the same tensile speed. The segregation of Re, W, Al, and Mo was intensified, while the segregation of Cr, Co, and Ta showed no significant change. Using argon gas protection and increasing the withdraw rate can increase the temperature gradient and growth rate during directional solidification, achieving the purpose of refining dendrite structure and reducing eutectic and pore content. The increase in temperature gradient by argon protection is about 3.4%-3.7%, so the optimization effect on cast structure is not particularly obvious. In contrast, increasing the withdraw rate is more obvious for optimizing the casting structure.

Key words

the third-generation nickel-based single-crystal superalloy / HRS directional solidification / withdraw rate / argon gas protection / as-cast structure / as-cast segregation

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ZHU Xiaolong, YU Zefeng, LI Ke, HUANG Xiaoming, CHEN Senhong, CHEN Haotian, WANG Xiaoshan, ZENG Long, XIA Mingxu, LI Jianguo. Influence of Directional Solidification Process Parameters on Casting Structure of Third-generation Nickel-based Single-crystal Superalloys[J]. Journal of Netshape Forming Engineering. 2025, 17(11): 37-46 https://doi.org/10.3969/j.issn.1674-6457.2025.11.003

References

[1] 张健, 王莉, 谢光, 等. 镍基单晶高温合金的研发进展[J]. 金属学报, 2023, 59(9): 1109-1124.
ZHANG J, WANG L, XIE G, et al.Recent Progress in Research and Development of Nickel-Based Single Crystal Superalloys[J]. Acta Metallurgica Sinica, 2023, 59(9): 1109-1124.
[2] 刘满平, 马辉, 崔壮, 等. 镍基单晶高温合金疲劳行为研究进展[J]. 稀有金属材料与工程, 2025, 54(8): 2151-2163.
LIU M P, MA H, CUI Z, et al.Review on Fatigue Behavior of Ni-Based Single Crystal Superalloys[J]. Rare Metal Materials and Engineering, 2025, 54(8): 2151-2163.
[3] 任能, 杨绿伟, 李军, 等. 高温合金定向凝固数值模拟研究进展[J]. 特种铸造及有色合金, 2023, 43(10): 1336-1350.
REN N, YANG L, LI J, et al.Research Progress in Numerical Simulation of Superalloys during Directional Solidification[J]. Special Casting & Nonferrous Alloys, 2023, 43(10): 1336-1350.
[4] WANG H Z, LONG H B, SUN M, et al.Effect of Directional Solidification Methods on Solid Solution Window in Ni-Based Single-Crystal Superalloy[J]. Journal of Materials Research and Technology, 2023, 24: 8307-8319.
[5] 任能. 镍基单晶高温合金定向凝固中杂晶和雀斑缺陷的预测与控制[D]. 上海: 上海交通大学, 2022.
REN N.Prediction and Control of Impurity Crystal and Freckle Defects in Directional Solidification of Nickel-based Single Crystal Superalloy[D]. Shanghai: Shanghai Jiao Tong University, 2022.
[6] LIU C B, SHEN J, ZHANG J, et al.Effect of Withdrawal Rates on Microstructure and Creep Strength of a Single Crystal Superalloy Processed by LMC[J]. Journal of Materials Science & Technology, 2010, 26(4): 306-310.
[7] KONTER M, THUMANN M.Materials and Manufacturing of Advanced Industrial Gas Turbine Components[J]. Journal of Materials Processing Technology, 2001, 117(3): 386-390.
[8] 刘林, 孙德建, 黄太文, 等. 高梯度定向凝固技术及其在高温合金制备中的应用[J]. 金属学报, 2018, 54(5): 615-626.
LIU L, SUN D J, HUANG T W, et al.Directional Solidification under High Thermal Gradient and Its Application in Superalloys Processing[J]. Acta Metallurgica Sinica, 2018, 54(5): 615-626.
[9] KONTER M, KATS E A, HOFMANN N.A Novel Casting Process for Single Crystal Gas Turbine Components[J]. Superalloys 2000,189-200.
[10] 刘林. 单晶高温合金高梯度定向凝固及组织优化[D]. 西安: 西北工业大学, 2017.
LIU L.Single Crystal High-Temperature Alloy High- Gradient Directional Solidification and Microstructure Optimization[D]. Xi'an: Northwestern Polytechnical University, 2017.
[11] 刘刚, 刘林, 赵新宝, 等. 一种镍基单晶高温合金的高温度梯度定向凝固组织及枝晶偏析[J]. 金属学报, 2010, 46(1): 77-83.
LIU G, LIU L, ZHAO X B, et al.Microstructure and Microsegregation in a Ni-Based Single Crystal Superalloy Directionally Solidified under High Thermal Gradient[J]. Acta Metallurgica Sinica, 2010, 46(1): 77-83.
[12] 赵运兴, 王迪, 马德新, 等. 枝晶细化对第三代单晶高温合金显微组织和持久性能的影响[J]. 稀有金属材料与工程, 2025, 509(19): 403-408.
ZHAO Y X, WANG D, MA D X, et al.Effect of Dendrite Refinement on the Microstructure and Stress Rupture Properties of a Third-Generation Single Crystal Superalloy[J]. Rare Metal Materials and Engineering, 2025, 509(19): 1002-185X.
[13] WANG B Q, ZENG L, REN N, et al.A Comprehensive Understanding of Grain Selection in Spiral Grain Selector during Directional Solidification[J]. Journal of Materials Science & Technology, 2022, 102: 204-212.
[14] 曹丙谦, 陈森鸿, 戚诚康, 等. NbSi基合金HRS法制备研究[J]. 精密成形工程, 2024, 16(10): 41-49.
CAO B Q, CHEN S H, QI C K, et al.Preparation of NbSi-Based Alloys by HRS Method[J]. Journal of Netshape Forming Engineering, 2024, 16(10): 41-49.
[15] 国家质量监督检验检疫总局, 中国国家标准化管理委员会. 高温合金铸件晶粒度、一次枝晶间距和显微疏松测定方法: GB/T 14999.7—2010[S]. 北京: 中国标准出版社, 2011.
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China. Test Methods for Grain Sizes, Primary Dendrite Spacing and Microshrinkage of Superalloy Castings: GB/T 14999.7—2010[S]. Beijing: Standards Press of China, 2011.
[16] MIRAK A, FATHI M.Effects of Solidification Rate and Heat Treatment on Microstructure Characterization and Hot Tensile Strength of Single Crystal CMSX-4 Superalloy[J]. Materials Characterization, 2022, 194: 112449.
[17] STRICKLAND J, NENCHEV B, DONG H B.On Directional Dendritic Growth and Primary Spacing—A Review[J]. Crystals, 2020, 10(7): 627.
[18] 齐永顺, 李丰文, 玄伟东, 等. 抽拉速率对DD5单晶高温合金定向凝固组织及偏析的影响[J]. 上海金属, 2022, 44(3): 65-71.
QI Y S, LI F W, XUAN W D, et al.Effect of Withdrawal Rate on Microstructures and Segregation of Directionally Solidified DD5 Single Crystal Superalloy[J]. Shanghai Metals, 2022, 44(3): 65-71.
[19] 于军伟. 不同抽拉速率下DD6单晶高温合金的组织、性能研究[D]. 上海: 上海交通大学, 2019.
YU J W.Microstructure and Properties of DD6 Single Crystal Superalloy at Different Withdrawing Rates[D]. Shanghai: Shanghai Jiao Tong University, 2019.
[20] 刘静姝, 王磊, 刘杨, 等. Co含量对一种新型高温合金铸态及热处理组织的影响[J]. 材料与冶金学报, 2023, 22(4): 351-360.
LIU J S, WANG L, LIU Y, et al.Effect of Co Content on the As-Cast and Heat-Treated Microstructure of a Novel Fourth-Generation Nickel-Based Single Crystal Superalloy[J]. Journal of Materials and Metallurgy, 2023, 22(4): 351-360.
[21] 马振. 微量调整Re含量对第二代镍基单晶高温合金组织和性能的影响[D]. 沈阳: 东北大学, 2020.
MA Z.Effect of Minor Re Adjustment on Microtructure and Mechanical Properties of the Second Generation Ni-based Single Crystal Superalloy[D]. Shenyang: Northeastern University, 2020.
[22] WAGNER A, SHOLLOCK B A, MCLEAN M.Grain Structure Development in Directional Solidification of Nickel-Base Superalloys[J]. Materials Science and Engineering: A, 2004, 374(1/2): 270-279.
[23] YAN B C, ZHANG J, LOU L H.Effect of Boron Additions on the Microstructure and Transverse Properties of a Directionally Solidified Superalloy[J]. Materials Science and Engineering: A, 2008, 474(1/2): 39-47.
[24] WALSTON W S, BERNSTEIN I M, THOMPSON A W.The Role of the γ'/γ Eutectic and Porosity on the Tensile Behavior of a Single-Crystal Nickel-Base Superalloy[J]. Metallurgical Transactions A, 1991, 22(6): 1443-1451.
[25] KEARSEY R M, AU P, BEDDOES J C, et al.The Effects of Re, W and Ru on Microsegregation Behaviour in Single Crystal Superalloy Systems[C]//Superalloys 2004 (Tenth International Symposium). TMS, 2004: 801-810.
[26] ROSKOSZ S, ADAMIEC J.Methodology of Quantitative Evaluation of Porosity, Dendrite Arm Spacing and Grain Size in Directionally Solidified Blades Made of CMSX-6 Nickel Alloy[J]. Materials Characterization, 2009, 60(10): 1120-1126.
[27] WHITESELL H S, OVERFELT R A.Influence of Solidification Variables on the Microstructure, Macrosegregation, and Porosity of Directionally Solidified Mar-M247[J]. Materials Science and Engineering: A, 2001, 318(1/2): 264-276.
[28] ZHAO Y S, ZHANG M, YANG L Y, et al.Effect of the Withdrawal Rate on the Microstructure and Thermal Durability of a Third-Generation Single Crystal Superalloy[J]. Progress in Natural Science: Materials International, 2021, 31(3): 493-500.
[29] GUO X P, FU H Z, SUN J H.Influence of Solid/Liquid Interfaces on the Microstructure and Stress-Rupture Life of the Single-Crystal Nickel-Base Superalloy NASAIR 100[J]. Metallurgical and Materials Transactions A, 1997, 28(4): 997-1009.
[30] 杜炜, 魏朋义, 李建国, 等. 中速生长条件下单晶高温合金组织及偏析研究[J]. 金属学报, 1998, 34(4): 356-361.
DU W, WEI P Y, LI J G, et al.Microstructure and Microsegregation of Ni-Base Single Crystal Superalloy Solidified at Medium Cooling Rate[J]. Acta Metallrugica Sinica, 1998, 34(4): 356-361.
[31] ZHANG J, LIU Y H, LI J G, et al.Directional Solidification of Monocrystal Superalloy by Electron Beam Floating Zone-Melting[J]. Journal of Materials Science, 1999, 34(11): 2507-2511.
[32] LIU G, LIU L, AI C, et al.Influence of Withdrawal Rate on the Microstructure of Ni-Base Single-Crystal Superalloys Containing Re and Ru[J]. Journal of Alloys and Compounds, 2011, 509(19): 5866-5872.