重型燃气轮机用定向凝固UGTC47合金近服役条件下的显微组织演化  

Microstructure evolution of directionally solidified UGTC47 alloy for heavy-duty gas turbines under near service conditions

作　　者：李家兴 陆民刚 束国刚 杨德宇 申茹茹 郑为为[1] LI Jia-xing;LU Min-gang;SHU Guo-gang;YANG De-yu;SHEN Ru-ru;ZHENG Wei-wei(State Key Laboratory for Advanced Metals and Materials,University of Science and Technology Beijing,Beijing 100083,China;China United Gas Turbine Technology Co Ltd,Beijing 100016,China)

机构地区：[1]北京科技大学新金属材料国家重点实验室,北京100083 [2]中国联合重型燃气轮机技术有限公司,北京100016

出　　处：《材料热处理学报》2025年第2期152-163,共12页Transactions of Materials and Heat Treatment

基　　金：中国联合重型燃气轮机技术有限公司资助项目(UGTC-HT-WXKT-2022-038)。

摘　　要：重型燃气轮机透平叶片长时服役过程中受温度和应力作用,将不可避免发生显微组织损伤。以国产定向凝固UGTC47合金为研究对象,研究其在850~950℃近服役温度范围内热暴露及热力耦合模拟1000、3000和5000 h后的显微组织演化。结果表明:经标准热处理的UGTC47合金在850~950℃热暴露及热力耦合模拟后,枝晶干γ′相的退化速度大于枝晶间区域的γ′相,枝晶干γ′相体积分数在退化初期就下降至60%左右;应力会促进γ′相体积分数趋于平衡状态,但在850、900和950℃热力耦合模拟5000 h下无显著差别,仍保持55%左右。γ′相尺寸基本符合LSW理论的生长模型。随着应力的增加和时间的延长,γ′相筏排化程度逐渐增大至0.6左右后趋于稳定,时间继续延长,甚至有所降低;γ相通道宽度随温度和应力增加呈线性增大趋势。During the long-term service of heavy-duty gas turbine blades,microstructural damage will inevitably occur due to temperature and stress effects.Microstructure evolution of domestically produced directionally solidified UGTC47 alloy after thermal exposure and thermal-stress coupling simulation at the near service temperature of 850-950 ℃ for 1000 h,3000 h and 5000 h was studied.The results show that after thermal exposure and thermal-stress coupling simulation at 850-950 ℃,the degradation rate of γ′ phase in dendrite core of the standard heat treated UGTC47 alloy is greater than that of in interdendritic regions,and the volume fraction of γ′ phase in dendrite core decreases to about 60% in the early stage of degradation.Stress can promote the γ′ phase volume fraction towards an equilibrium state,but there is no significant difference after 5000 h of thermal-stress coupling simulation at 850 ℃,900 ℃ and 950 ℃,still maintaining about 55%.The size of γ′ phase basically conforms to the growth model of LSW theory.As the stress and time increase,the rafting degree of γ′ phase gradually increases to about 0.6,then stabilizes,or even decreases with the time further increases.The channel width of γ phase shows a linear increasing trend with increasing temperature and stress.

关 键 词：定向凝固UGTC47合金 重型燃气轮机 近服役温度 热力耦合 显微组织 

分 类 号：TG132.3[一般工业技术—材料科学与工程]