冷却速率导致的薄壁效应对<strong>K465</strong>合金显微组织和持久性能的影响

doi:10.11900/0412.1961.2020.00147

金属学报

2020, Vol. 56

Issue (12): 1654-1666 DOI: 10.11900/0412.1961.2020.00147

本期目录 | 过刊浏览

冷却速率导致的薄壁效应对K465合金显微组织和持久性能的影响

郭小童¹^,², 郑为为¹, 李龙飞¹, 冯强¹(

)

1 北京科技大学新金属材料国家重点实验室北京 100083
2 中国电子产品可靠性与环境试验研究所广州 510610

Cooling Rate Driven Thin-Wall Effects on the Microstructures and Stress Rupture Properties of K465 Superalloy

GUO Xiaotong¹^,², ZHENG Weiwei¹, LI Longfei¹, FENG Qiang¹(

)

1 State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China
2 China Electronic Product Reliability and Environmental Testing Research Institute, Guangzhou 510610, China

引用本文:

郭小童, 郑为为, 李龙飞, 冯强. 冷却速率导致的薄壁效应对K465合金显微组织和持久性能的影响[J]. 金属学报, 2020, 56(12): 1654-1666.
Xiaotong GUO, Weiwei ZHENG, Longfei LI, Qiang FENG. Cooling Rate Driven Thin-Wall Effects on the Microstructures and Stress Rupture Properties of K465 Superalloy[J]. Acta Metall Sin, 2020, 56(12): 1654-1666.

全文: PDF(5874 KB) HTML

摘要:

航空发动机涡轮叶片内部的复杂气膜冷却系统使得叶片叶身部位壁厚越来越薄，导致其显微组织和力学性能与传统模拟材料(如实心标准试棒)存在明显差异。本工作利用铸造成型的K465合金空心管材模拟空心叶片叶身的显微组织，对其进行900~1050 ℃、300~1000 h热暴露处理，并测试热暴露前后在975 ℃、225 MPa条件下的持久性能。利用OM、SEM、TEM和XRD观察和表征热暴露前后的显微组织，利用物理化学相分析的方法测量析出相的化学成分，研究热暴露过程中显微组织的演变规律及其对持久性能的影响。结果表明：在900~1050 ℃热暴露过程中，K465合金管材中主要发生γ'相的溶解和粗化连接、MC型碳化物的分解以及晶界γ'膜的宽化；随着热暴露温度的升高和时间的延长，γ'相、碳化物和晶界的退化程度逐渐加剧，导致合金的持久寿命逐步降低。与已有文献报道的900 ℃热暴露时标准试棒中μ相大量析出的现象不同，管材中并未析出μ相；1000和1050 ℃热暴露后，管材和棒材组织退化程度接近。900 ℃热暴露时，冷却速率导致的薄壁效应对K465合金的显微组织和持久性能影响显著；而1000和1050 ℃热暴露时，薄壁效应不明显。本工作的研究成果为等轴晶铸造高温合金涡轮叶片的生产和服役损伤评价提供了参考依据。

关键词 ： K465合金, 涡轮叶片, 薄壁效应, 显微组织, 持久性能

Abstract：

The designed service temperature of turbine blades is rising with the increasing thrust of aircraft engines. A film cooling system is one of the promising ways to improve the service temperature of turbine blades. However, such a complex film cooling system can reduce the thickness of the blade airfoil and lead to obvious local differences in microstructure; these differences are caused by solidification and mechanical resistance between the blade airfoil and alloys such as standard solid bars. In this study, a thin-walled tube manufactured by the casting process was used to simulate the microstructure of the hollow blade airfoil. The tube was thermally exposed at a temperature range of 900~1050 ℃ for 300~1000 h, and the corresponding stress rupture properties under 975 ℃ and 225 MPa (pressure) were examined. The microstructures were investigated using OM, SEM, TEM, and XRD, and the chemical compositions of the precipitates formed were measured through physicochemical phase analysis before and after the thermal exposure. Through this analysis, the relationship between microstructural degradation and stress rupture properties was revealed. The results indicated that dissolution and coarsening of γ' precipitates, degeneration of MC carbides, and broadening of the γ' film along the grain boundaries occurred in the K465 alloy tube during thermal exposure between 900 ℃ and 1050 ℃. With increasing exposure temperatures and prolonged thermal exposure time, the degree of degradation of the γ' precipitates, carbides, and grain boundaries gradually increased. This resulted in a gradual reduction in stress rupture lives. Unlike the phenomenon observed in our previous study in which a large amount of μ phase precipitated in the solid bar following thermal exposure at 900 ℃; in the present study, the μ phase did not form in the tube. However, the degrees of microstructural degradation in the tube and bar were similar after the thermal exposure at 1000 and 1050 ℃. The stress rupture lives of the tube were significantly higher than those of the bar after the thermal exposure at 900 ℃, whereas their stress rupture lives were similar after the thermal exposure at 1000 and 1050 ℃. The thin-wall effect caused by the cooling rate on the microstructure and the corresponding stress rupture property of K465 alloy was obvious at 900 ℃, whereas it was negligible at 1000 and 1050 ℃. These results provided guidance for the manufacturing and evaluation of microstructural degradation of turbine blades made of conventionally cast polycrystalline superalloys.

Key words： K465 alloy turbine blade thin-wall effect microstructure stress rupture property

收稿日期: 2020-05-06

ZTFLH:

TG146.1

基金资助:国家重点研发计划项目(2016YFB0701403);国家自然科学基金项目(51631008);国家自然科学基金项目(91860201)

作者简介: 郭小童，男，1988年生，博士

	服务

	把本文推荐给朋友
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	郭小童
	郑为为
	李龙飞
	冯强
44.8K

链接本文:

https://www.ams.org.cn/CN/10.11900/0412.1961.2020.00147 或 https://www.ams.org.cn/CN/Y2020/V56/I12/1654

图1 K465合金管材持久试样示意图

图2 K465合金管材经标准热处理后的典型显微组织(a) OM image (b) SEM-SE image of γ' precipitates in the dendrite core region(c) SEM-BSE image of carbides in the interdendritic region (d) SEM-BSE image of grain boundary

表1 K465合金管材经标准热处理和900~1050 ℃热暴露后枝晶干γ'相的面积分数(Af)和晶界γ'膜的宽度(W)

图3 K465合金管材经不同热暴露处理后枝晶干γ'相的SEM-SE像(a) 900 ℃, 1000 h (b) 1000 ℃, 1000 h (c) 1050 ℃, 300 h (d) 1050 ℃, 1000 h

图4 K465合金管材经不同热暴露处理后枝晶间区域的SEM像

图5 K465合金管材经1000 ℃、1000 h热暴露后枝晶间碳化物的TEM像及SAED花样

图6 K465合金管材经不同热暴露处理后晶界的SEM像

图7 K465合金管材标准热处理态和经1000 ℃、1000 h热暴露后萃取碳化物粉末的XRD谱(a) after the standard heat treatment (b) after thermal exposure at 1000 ℃ for 1000 h

图8 K465合金管材标准热处理态和经900 ℃、1000 h及1000 ℃、1000 h热暴露后碳化物的质量分数

表2 K465合金管材经标准热处理和900 ℃、1000 h及1000 ℃、1000 h热暴露后，通过物理化学相分析方法测量得到的碳化物化学成分 (atomic fraction / %)

图9 K465合金棒材[14]、管材标准热处理态和经900~1050 ℃热暴露后975 ℃、225 MPa条件下的持久寿命

图10 K465合金管材经不同热暴露处理后在持久实验后近断口纵截面裂纹的SEM-BSE像(a) 900 ℃, 500 h (b, c) 1000 ℃, 500 h

图11 根据Thermo-Calc软件计算得到的K465合金在700~1400 ℃范围内的相组成-温度平衡相图

表3 根据Thermo-Calc软件计算得到的K465合金管材在700~1400 ℃范围内二次相析出温度及质量分数

[1]	Bunker R S, Wallace T T. Turbine airfoil with double shell outer wall [P]. US Pat, 5328331A, 1994
[2]	Jackson M R, Skelly D W, Rowe R G, et al. Double wall turbine parts [P]. US Pat, 5820337A, 1998
[3]	Bunker R S, Huang S C, Klug F J. Cooling of a double walled turbine blade and method of fabrication [P]. EP Pat, 1369554A1, 2003
[4]	Liang G. Thin turbine rotor blade with sinusoidal flow cooling channels [P]. US Pat, 7753650 B1, 2010
[5]	Chung V, Ortiz M, Poon K. Thin wall cooling system [P]. US Pat, 6478535 B1, 2002
[6]	Zheng Y R. Size effects of thin section for single crystal turbine blade superalloys [J]. J. Mater. Eng., 2007, (7): 74
[6]	(郑运荣. 单晶涡轮叶片合金的薄截面尺寸效应 [J]. 材料工程, 2007, (7): 74)
[7]	Seetharaman V, Cetel A D. Thickness debit in creep properties of PWA 1484 [A]. Superalloys 2004: Proceedings of the 10th International Symposium on Superalloys [C]. Seven Springs, Pennsylvania: TMS, 2004: 207
[8]	Duhl D N. Directionally solidified superalloys [A]. Superalloys II High Temperature Materials for Aerospace and Industrial Power [C]. New York: John Wiley and Sons, 1987: 189
[9]	Zheng Y R, Cai Y L. Notable problems in microstructure analysis of superalloy castings [J]. J. Mater. Eng., 1982, (6): 29
[9]	(郑运荣, 蔡玉林. 高温合金铸件显微组织分析中值得注意的问题 [J]. 材料工程, 1982, (6): 29)
[10]	Pal J, Srinivasan D, Cheng E. Effect of rejuvenation heat treatment and aging on the microstructural evolution in René N5 single crystal Ni base superalloy blades [A]. Superalloys 2016: Proceedings of the 13th International Symposium of Superalloys [C]. Seven Springs, Pennsylvania: TMS, 2016: 285
[11]	Brunner M, Bensch M, Völkl R, et al. Thickness influence on creep properties for Ni-based superalloy M247LC SX [J]. Mater. Sci. Eng., 2012, A550: 254
[12]	Academic Committee of the Superalloys, CSM. China Superalloys Handbook [M]. Beijing: Standards Press of China, 2012: 232
[12]	(中国金属学会高温材料分会. 中国高温合金手册 [M]. 北京: 中国标准出版社, 2012: 232)
[13]	Yuan X F, Song J X, Zheng Y R, et al. Abnormal stress rupture property in K465 superalloy caused by microstructural degradation at 975 ℃/225 MPa [J]. J. Alloys Compd., 2016, 662: 583 doi: 10.1016/j.jallcom.2015.12.086
[14]	Yuan X F, Song J X, Zheng Y R, et al. Quantitative microstructural evolution and corresponding stress rupture property of K465 superalloy [J]. Mater. Sci. Eng., 2016, A651: 734
[15]	Yang J X, Zheng Q, Sun X F, et al. Morphological evolution of γ' phase in K465 superalloy during prolonged aging [J]. Mater. Sci. Eng., 2007, A457: 148
[16]	Yang J X, Zheng Q, Sun X F, et al. Formation of μ phase during thermal exposure and its effect on the properties of K465 superalloy [J]. Scr. Mater., 2006, 55: 331 doi: 10.1016/j.scriptamat.2006.04.032
[17]	Guo X T, Zheng W W, Xiao C B, et al. Evaluation of microstructural degradation in a failed gas turbine blade due to overheating [J]. Eng. Fail. Anal., 2019, 103: 308 doi: 10.1016/j.engfailanal.2019.04.021
[18]	Yuan X F. The assessment of normal service induced damage in high pressure turbine blades made of equiaxed crystal cast superalloy K465 [D]. Beijing: University of Science and Technology Beijing, 2015
[18]	(袁晓飞. 等轴晶铸造K465合金高压涡轮叶片正常服役损伤及其评价研究 [D]. 北京: 北京科技大学, 2015)
[19]	Guo X T, Antonov S, Lu F, et al. Solidification rate driven microstructural stability and its effect on the creep property of a polycrystalline nickel-based superalloy K465 [J]. Mater. Sci. Eng., 2020, A770: 138530
[20]	Jeong H W, Seo S M, Choi B G, et al. Effect of long-term thermal exposures on microstructures and mechanical properties of directionally solidified CM247LC alloy [J]. Met. Mater. Int., 2013, 19: 917 doi: 10.1007/s12540-013-5003-5
[21]	Cheng K Y, Jo C Y, Kim D H, et al. Influence of local chemical segregation on the γ′ directional coarsening behavior in single crystal superalloy CMSX-4 [J]. Mater. Charact., 2009, 60: 210 doi: 10.1016/j.matchar.2008.09.002
[22]	Sun W, Qin X Z, Guo J T, et al. Thermal stability of primary MC carbide and its influence on the performance of cast Ni-base superalloys [J]. Mater. Des., 2015, 69: 81 doi: 10.1016/j.matdes.2014.12.038
[23]	Qin X Z, Guo J T, Yuan C, et al. Long-term thermal exposure responses of the microstructure and properties of a cast Ni-base superalloy [J]. Mater. Sci. Eng., 2012, A543: 121
[24]	Reed R C. The Superalloys: Fundamentals and Applications [M]. New York: Cambridge University Press, 2006: 90
[25]	Godovanets M A, Prusakov B A, Lysenko I I. Regenerative heat treatment of blades of high-temperature nickel alloys [J]. Met. Sci. Heat Treat., 1996, 38: 202 doi: 10.1007/BF01397020
[26]	Johnston J R, Dreshfield R L, Collins H E. Effect of casting geometry on mechanical properties of two nickel-base superalloys [R]. Ohio: NACA Technical Memorandum X-3386, 1976
[27]	Lloyd R D. The effect of casting variables and section size on the stress-rupture life of a high temperature nickel base alloy [A]. AIME Spring Meeting [C]. Pittsburgh: SAE International, 1969: 1
[28]	Bensch M, Fleischmann E, Konrad C H, et al. Secondary creep of thin-walled specimens affected by oxidation [A]. Superalloys 2012: Proceedings of the 12th International Symposium on Superalloys [C]. Seven Springs, Pennsylvania: TMS, 2012: 387
[29]	Yang J X, Zheng Q, Sun X F, et al. Morphological evolution of MC carbide in K465 superalloy [J]. J. Mater. Sci., 2006, 41: 6476 doi: 10.1007/s10853-006-0684-5
[30]	Yang J X, Zheng Q, Sun X F, et al. Morphological evolution of γ′ phase in K465 superalloy during thermal fatigue [J]. Trans. Nonferrous Met. Soc. China, 2006, 16: 1986
[31]	Wang F, Ma D X, Bührig-Polaczek A. Eutectic formation during solidification of Ni-based single-crystal superalloys with additional carbon [J]. Metall. Mater. Trans., 2017, 48A: 5442
[32]	Gong L, Chen B, Zhang L, et al. Effect of cooling rate on microstructure, microsegregation and mechanical properties of cast Ni-based superalloy K417G [J]. J. Mater. Sci. Technol., 2018, 34: 811 doi: 10.1016/j.jmst.2017.03.023

[1]	张雷雷, 陈晶阳, 汤鑫, 肖程波, 张明军, 杨卿. K439B铸造高温合金800℃长期时效组织与性能演变[J]. 金属学报, 2023, 59(9): 1253-1264.
[2]	卢楠楠, 郭以沫, 杨树林, 梁静静, 周亦胄, 孙晓峰, 李金国. 激光增材修复单晶高温合金的热裂纹形成机制[J]. 金属学报, 2023, 59(9): 1243-1252.
[3]	孙蓉蓉, 姚美意, 王皓瑜, 张文怀, 胡丽娟, 仇云龙, 林晓冬, 谢耀平, 杨健, 董建新, 成国光. Fe22Cr5Al3Mo-xY合金在模拟LOCA下的高温蒸汽氧化行为[J]. 金属学报, 2023, 59(7): 915-925.
[4]	吴东江, 刘德华, 张子傲, 张逸伦, 牛方勇, 马广义. 电弧增材制造2024铝合金的微观组织与力学性能[J]. 金属学报, 2023, 59(6): 767-776.
[5]	张东阳, 张钧, 李述军, 任德春, 马英杰, 杨锐. 热处理对选区激光熔化Ti55531合金多孔材料力学性能的影响[J]. 金属学报, 2023, 59(5): 647-656.
[6]	李殿中, 王培. 金属材料的组织定制[J]. 金属学报, 2023, 59(4): 447-456.
[7]	张子轩, 于金江, 刘金来. 镍基单晶高温合金DD432的持久性能各向异性[J]. 金属学报, 2023, 59(12): 1559-1567.
[8]	芮祥, 李艳芬, 张家榕, 王旗涛, 严伟, 单以银. 新型纳米复合强化9Cr-ODS钢的设计、组织与力学性能[J]. 金属学报, 2023, 59(12): 1590-1602.
[9]	朱智浩, 陈志鹏, 刘田雨, 张爽, 董闯, 王清. 基于不同 α / β 团簇式比例的Ti-Al-V合金的铸态组织和力学性能[J]. 金属学报, 2023, 59(12): 1581-1589.
[10]	彭立明, 邓庆琛, 吴玉娟, 付彭怀, 刘子翼, 武千业, 陈凯, 丁文江. 镁合金选区激光熔化增材制造技术研究现状与展望[J]. 金属学报, 2023, 59(1): 31-54.
[11]	葛进国, 卢照, 何思亮, 孙妍, 殷硕. 电弧熔丝增材制造2Cr13合金组织与性能各向异性行为[J]. 金属学报, 2023, 59(1): 157-168.
[12]	杨天野, 崔丽, 贺定勇, 黄晖. 选区激光熔化AlSi10Mg-Er-Zr合金微观组织及力学性能强化[J]. 金属学报, 2022, 58(9): 1108-1117.
[13]	张鑫, 崔博, 孙斌, 赵旭, 张欣, 刘庆锁, 董治中. Y元素对Cu-Al-Ni高温形状记忆合金性能的影响[J]. 金属学报, 2022, 58(8): 1065-1071.
[14]	刘仁慈, 王鹏, 曹如心, 倪明杰, 刘冬, 崔玉友, 杨锐. 700℃热暴露对 β 凝固 γ-TiAl合金表面组织及形貌的影响[J]. 金属学报, 2022, 58(8): 1003-1012.
[15]	李彦强, 赵九洲, 江鸿翔, 何杰. Pb-Al合金定向凝固组织形成过程[J]. 金属学报, 2022, 58(8): 1072-1082.

Viewed

Full text

Abstract

Cited

Shared

Discussed