摘要
采用真空离心铸造技术制备了K418高温合金细晶铸环,并对其微观结构、力学性能及断裂行为进行了研究。该离心铸坯晶粒度达4级,并均匀分布着尺寸为200~300 nm的γ'相。结合数值模拟结果,分析了高速旋转产生的梯度流场和快速冷却条件对充型凝固过程和晶粒组织的影响。等轴晶区表现出优异的力学性能,抗拉强度达1 115.5 MPa,伸长率为12.4%。断口分析揭示了以微孔聚合为主的断裂机制,裂纹沿晶界、γ/γ'界面、碳化物周围及γ/γ'共晶相扩展。
The microstructure,mechanical properties,and fracture behavior of fine-crystalline K418 superalloy ring prepared by vacuum centrifugal casting technology were investigated.The cast ring exhibits grain size of ASTM 4,with uniformly distributedγ'precipitates with diameter of 200~300 nm.Numerical simulation was employed to eluci⁃date the effects of gradient flow fields induced by high-speed rotation and rapid cooling on the solidification process and microstructure.Superior mechanical properties are achieved in equiaxed region,where the tensile strength and elonga⁃tion reach up to 1115.5 MPa and 12.4%,respectively.Fractographic analysis reveals that fracture mechanism is domi⁃nated by microvoid coalescence,with crack propagation along grain boundaries,γ/γ'interfaces,carbide peripheries,andγ/γ'eutectic phase.
作者
陈斗南
陈奕帆
吴岱霖
王怡然
王宇航
刘国怀
CHEN Dounan;CHEN Yifan;WU Dailin;WANG Yiran;WANG Yuhang;LIU Guohuai(School of Materials Science and Engineering,Northeastern University,Shenyang 110819;College of Chemical Engineering and Environment,Shenyang Ligong University,Shenyang 110159;State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819)
出处
《特种铸造及有色合金》
北大核心
2025年第11期1715-1721,共7页
Special Casting & Nonferrous Alloys
基金
国家自然科学基金资助项目(52071065)
中央高校基本科研业务费资助项目(N2007007)
国家重点研发计划资助项目(2016YFB-0301201)
工信部重点新材料研发及应用国家科技重大专项(2025ZD0610001)。
关键词
K418高温合金
真空离心铸造
微观组织
力学性能
数值模拟
K418 Superalloy
Vacuum Centrifugal Casting
Microstructure
Mechanical Properties
Numerical Simulation
