Segregation of as-cast microstructure and homogenization treatment of GH6783 Co-based superalloy

doi:10.13251/j.issn.0254-6051.2024.12.031

Abstract

Abstract: Precipitates, homogenization temperature and homogenization time of GH6783 superalloy were calculated by JMatPro software. Microstructure of the as-cast and homogenized alloy and the segregation behavior of elements were analyzed and characterized by means of optical microscope, scanning electron microscope and energy dispersive spectrometer, in order to analyze evolution law of microstructure and segregation coefficient during the homogenization process of the GH6783 superalloy. The results show that major precipitates of the GH6783 superalloy include low-melting brittle phase(Laves phase), NiAl phase, et al. Nb element is the most serious segregation element of the as-cast GH6783 superalloy, with segregation coefficient up to 2.205, and Ti element is secondly serious. Nb and Ti elements are positive segregation element, and Cr, Fe and Co are negative segregation. Two stage homogenization treatment at 1130 ℃ for 4 h and 1190 ℃ for 32 h can dissolve Laves phase and make element diffusion uniformly of the as-cast GH6783 superalloy. After homogenization, segregation coefficient of Nb element decreases to 1.048.

Key words: GH6783 superalloy, homogenization, as-cast, segregation

CLC Number:

TG132.3

Qi Huilin, Jiang Shichuan, Guo Xulong, Tang Pingmei. Segregation of as-cast microstructure and homogenization treatment of GH6783 Co-based superalloy[J]. Heat Treatment of Metals, 2024, 49(12): 184-190.

References

[1]贾新云, 赵宇新, 张绍维. 抗氧化低膨胀高温合金GH6783[C]//动力与能源用高温结构材料——第十一届中国高温合金年会论文集. 中国高温合金年会, 2007: 290-293.
[2]贾若飞, 李梁, 秦承鹏. 某1000MW超超临界机组汽轮机IN783螺栓断裂失效分析[J]. 汽轮机技术, 2019, 61(1): 78-80, 12.
Jia Ruofei, Li Liang, Qin Chengpeng. Failure analysis of IN783 alloy bolt used on 1000MW ultra supercritical steam turbine[J]. Turbine Technology, 2019, 61(1): 78-80, 12.
[3]刘永民. 超超临界1000MW汽轮机GH783螺栓检修工艺优化[J]. 电力安全技术, 2019, 21(3): 54-56.
Liu Yongmin. The optimization of GH783 bolts on-site maintenance process of ultra-supercritical 1000MW steam turbine[J]. Electric Safety Technology, 2019, 21(3): 54-56.
[4]孙雄, 杨超, 杨贤彪. 汽轮机IN783合金螺栓的断裂行为[J]. 理化检验(物理分册), 2018, 54(11): 785-789, 810.
Sun Xiong, Yang Chao, Yang Xianbiao. Fracture behavior of IN783 alloy bolts in steam turbine[J]. Physical Testing and Chemical Analysis(Part A: Physical Testing), 2018, 54(11): 785-789, 810.
[5]韩光炜, 冯涤, 邓波. 抗氧化低膨胀高温合金In783持久断裂行为的研究[C]//2000年材料科学与工程新进展(下)——2000年中国材料研讨会论文集. 中国材料研讨会, 2000: 1026-1031.
[6]段辉, 甄小辉, 吴锐红. 热处理对IN783合金组织和拉伸性能的影响[J]. 热加工工艺, 2012, 41(2): 204-207.
Duan Hui, Zhen Xiaohui, Wu Ruihong. Effect of heat treatment on microstructure and tensile properties of IN783 alloy[J]. Hot Working Technology, 2012, 41(2): 204-207.
[7]丁雨田, 豆正义, 高钰璧, 等. 均匀化态GH3625合金熔化和凝固过程中的相变[J]. 材料研究学报, 2017, 31(11): 853-859.
Ding Yutian, Dou Zhengyi, Gao Yubi, et al. Phase transformation during melting and solidifying process of homogenized superalloy GH3625[J]. Chinese Journal of Materials Research, 2017, 31(11): 853-859.
[8]史松宜, 张亚玮, 吕旭东. 固溶处理对激光选区熔化In 718合金组织及持久性能的影响[J]. 材料热处理学报, 2020, 41(6): 69-76.
Shi Songyi, Zhang Yawei, Lü Xudong. Effect of solid solution treatment on microstructure and stress rupture properties of Inconel 718 alloy fabricated by selective laser melting[J]. Transactions of Materials and Heat Treatment, 2020, 41(6): 69-76.
[9]董建新, 李林翰, 李浩宇, 等. 高温合金铸锭均匀化程度对开坯热变形的再结晶影响[J]. 金属学报, 2015, 51(10): 1207-1218.
Dong Jianxin, Li Linhan, Li Haoyu, et al. Effect of extent of homogenization on the hot deformation recrystallization of superalloy ingot in cogging process[J]. Acta Metallurgica Sinica, 2015, 51(10): 1207-1218.
[10]戚慧琳, 蒋世川, 郭续龙. 均匀化工艺对GH5188铸态组织及力学性能的影响[J]. 金属热处理, 2023, 48(2): 158-165.
Qi Huilin, Jiang Shichuan, Guo Xulong. Effect of homogenization treatment on microstructure and mechanical properties of GH5188 alloy[J]. Heat Treatment of Metals, 2023, 48(2): 158-165.
[11]肖东平, 周扬, 付建辉, 等. GH141合金的凝固偏析特性及均匀化处理[J]. 金属热处理, 2022, 47(5): 141-147.
Xiao Dongping, Zhou Yang, Fu Jianhui, et al. Solidification segregation characteristic and homogenization treatment of GH141 superalloy[J]. Heat Treatment of Metals, 2022, 47(5): 141-147.
[12]兰博, 张国栋, 张学军, 等. 均匀化热处理对电子束熔丝增材制造GH4169合金组织和性能的影响[J]. 热加工工艺, 2019, 48(22): 167-171.
Lan Bo, Zhang Guodong, Zhang Xuejun, et al. Effects of homogenization heat treatment on microstructure and mechanical properties of GH4169 alloy fabricated by electron beam additive manufacturing[J]. Hot Working Technology, 2019, 48(22): 167-171.

[1]	Zhang Wei, Chen Zijian, Lin Yongcheng. Effect of homogenization on microstructure of 3003 aluminium alloy ingot [J]. Heat Treatment of Metals, 2024, 49(9): 236-241.
[2]	Wang Gang, Yang Shunming, Kuang Guanghui. Homogenization for 3105 aluminium alloy ingots [J]. Heat Treatment of Metals, 2024, 49(8): 200-203.
[3]	Liu Huashen, Sun Youping, He Jiangmei, Luo Guojian, Pei Mengyu. Effect of Al content and homogenization on microstructure and damping properties of Mg-Al binary alloys [J]. Heat Treatment of Metals, 2024, 49(7): 70-77.
[4]	Du Simin, Cheng Wenxiong, Hu Fengrong, Ren Jinqiao, Cui Xiaokang, Zhou Zhiming. Element segregation and homogenization heat treatment of DIEVAR hot working die steel [J]. Heat Treatment of Metals, 2024, 49(7): 139-145.
[5]	Chen Suming, Yue Shan, Hu Shengshuang, Zhao Hu, Li Yi, Wu Haifeng, Ouyang Delai. Strip segregation in PH13-8Mo stainless steel and its evolution during heat treatment [J]. Heat Treatment of Metals, 2024, 49(7): 152-156.
[6]	Guo Dayong, Gao Hang, Pan Yang, Gong Wenhe, Wang Bingxi, Yang Yingqiang. Control of grain boundary cementite of high carbon steel wire rods based on carbon segregation index [J]. Heat Treatment of Metals, 2024, 49(7): 287-293.
[7]	Ma Liang, Sun Ning, Ma Junxing, Chen Tongshuai, Guo Fengjia, Wang Jingtao. Homogenization process of high magnesium Al-Mg series aluminum alloy [J]. Heat Treatment of Metals, 2024, 49(6): 100-105.
[8]	Dong Na, Xu Zhoujue, Li Xiangjun, Zhou Wufeng, Chen Qifang, Tan Ruiqi, Yang Xiyang. Analysis on crack causes of 30CrMnSiA steel ring support [J]. Heat Treatment of Metals, 2024, 49(4): 293-296.
[9]	Du Yunfei, Bai Rui, Wu Pu, Zhang Yaqin. Microscopic characteristics of banded structure in PCrNi3MoV high-strength steel in quenching and tempering [J]. Heat Treatment of Metals, 2024, 49(3): 135-140.
[10]	Li Dongyang, Li Yanxia. Homogenization annealing process of Al-Si-Mg-B-Sr alloy [J]. Heat Treatment of Metals, 2024, 49(2): 199-202.
[11]	Yang Jiandong, Xie Bijun, Xu Bin, Sun Mingyue, Li Dianzhong. Effect of Ce content on inclusions and as-cast microstructure and hardness of S355NL low alloy steel [J]. Heat Treatment of Metals, 2024, 49(12): 122-127.
[12]	Xue Renjie, Dong Yikang, Ma Ziyang, Cao Xiao'en, Li Zhi'ang. Effect of banded structure on mechanical properties of cold-rolled dual phase steel DP780 [J]. Heat Treatment of Metals, 2024, 49(12): 191-197.
[13]	Du Lin, Wang Dihe, Pang Qihang, Zhong Lili, Yu Jiayao, Zhang Hongliang, Zhao Lidong. Effect of microstructure characteristics on yield ratio of 9Ni steel used in LNG storage tanks with a capacity of 200 000 cubic meters [J]. Heat Treatment of Metals, 2024, 49(12): 198-205.
[14]	Zuo Pengpeng, Yue Bin, Zhu Yuefan, Tang Yuxuan, Zhang Pan, Guo Fuyu, Min Na. Effect of high temperature diffusion annealing on microstructure and impact property of 4Cr5Mo2V hot working die steel [J]. Heat Treatment of Metals, 2024, 49(11): 123-131.
[15]	Yin Litao, Wang Jiuhua, Li Zhilong, Li Jie, Guo Yafei, Pang Qinghai. Preparation process, microstructure and properties of 00Cr23Ni12Mn5Mo2N austenitic stainless steel [J]. Heat Treatment of Metals, 2024, 49(11): 203-208.