金属加工（热加工）Issue(9)：73-80,90,9.
超高温气冷堆用Haynes230合金高温蠕变机制及显微组织演变
High-temperature creep mechanism and microstructure evolution of Haynes230 alloy for ultrahigh-temperature gas-cooled reactors
摘要
Abstract
Ultrahigh-temperature gas-cooled reactor(HTGR)is one of the key reactor types in the research and development of Generation Ⅳ nuclear energy systems,and the core outlet temperature reaches 800～950℃,which makes the working temperature of the intermediate heat exchanger(IHX)increase significantly.Haynes230 alloy is a competitive candidate for the IHX tubes,the evaluation of the creep-resistant properties of the alloy is of great significance for operating safely at high temperatures and high pressures over a long period of time.High temperature creep test of Haynes230 alloy was carried out at 800～950℃,the creep behavior and microstructure characterization were analyzed.The creep index n is between 3 and 7 obtained from the relationship of steady state creep rate and stress at 800～950 ℃,which inferred that the alloy creep mechanism for dislocation slip and climbing.The Monkan-Grant relationship model of Haynes230 alloy was established based on the relationship between steady state creep rate and creep rupture time.It can be seen that the growth of crack cavities inside the alloy during the creep process leads to the reduction of the effective area and causes fracture from the relationship between creep damage tolerance and creep rupture time of Haynes230 alloy.The main precipitated phase in Haynes230 alloy after solid solution is W-rich M6C distributed near the grain boundaries;granular M23C6 and M6C precipitated in the alloy during the creep process.The creep cracks originate from the coarse carbides on the grain boundaries,which extend perpendicularly to the direction of the force or along the stripe carbide extension.Transmission electron microscopy(TEM)analysis showed that dislocations slipped from the grain interior to the grain boundaries,and a large number of dislocations accumulated on the grain boundaries,which induce local stress concentration and initiation and propagation of cracks.关键词
Haynes230合金/蠕变/断裂机制/微观裂纹Key words
Haynes 230 alloy/creep/fracture mechanism/microcrack引用本文复制引用
刘林,杨亚倩,欧美琼,王旻,马颖澈,郑博文,郝宪朝..超高温气冷堆用Haynes230合金高温蠕变机制及显微组织演变[J].金属加工（热加工）,2025,(9):73-80,90,9.基金项目
中国科学院战略性先导科技专项项目(XDA0410000) （XDA0410000）
中核集团领创科研资助项目(41CNNC-LCKY-202278). （41CNNC-LCKY-202278）
