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第36卷第7期 北京科技大学学报 Vol.36 No.7 2014年7月 Journal of University of Science and Technology Beijing Jul.2014 FGH98合金的再结晶行为 李 昕,张麦仓区,李伟,董建新,郑 磊,姚志浩 北京科技大学材料科学与工程学院,北京100083 ☒通信作者,E-mail:nczhang(@usth.cdu.cn 摘要利用扫描电镜和透射电镜对热挤压态和退火态FGH98合金的相析出规律及组织特征进行了分析,并对其再结晶机 制进行了深入研究.结果表明:热挤压态GH98合金在空冷过程中已经发生了少量的再结晶现象,随着挤压温度的提高,体 系内位错密度下降.退火态FGH98合金中再结晶机制主要与体系内未回溶的一次y相有关,在一次γy相聚集区再结晶主要 以依靠亚晶的聚合和亚晶的长大,或两者的混合机制进行形核:随着一次y相的减少,合金还可以通过应变诱发晶界迁移、多 晶粒交汇区形核、孪晶叠加等多种方式形核.需要指出的是,FGH98合金中未回溶的一次y相在退火处理过程中也会通过部 分的回复和再结晶发生软化效应. 关键词高温合金;镍合金;挤压:退火:再结晶:软化 分类号TG146.15 Recrystallization behaviors of FGH98 alloy LI Xin,ZHANG Mai-eang,LI Wei,DONG Jian-xin,ZHENG Lei,YAO Zhi-hao School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China Corresponding author,E-mail:mczhang@ustb.edu.cn ABSTRACT The precipitated phase behavior,microstructure characteristics and static recrystallization mechanisms of FGH98 alloy in extruding and annealing states were systematically investigated by scanning electron microscopy (SEM)and transmission electron microscopy (TEM).A portion of recrystallized grains were observed in as-extruded samples during the cooling process,and the dislo- cation density decreases with the increasing of deformation temperature.The recrystallization mechanism of FGH98 alloy during the an- nealing process is mainly dominated by residual primary y'phase.In the region with a more content of residual primary y'phase,static recrystallization is controlled by the coalescence and growth of subgrains;when residual primary y'phase in the alloy decreases,many nucleation mechanisms of static recrystallization may occur,such as strain-induced boundary migration (SIBM),nucleation in the juncture of several grains,and twins superposition nucleation.It must be pointed out that residual primary yphase in the alloy can al- so be softened to somewhat extent by recovery and recrystallization during the annealing process. KEY WORDS superalloys;nickel alloys:extruding:annealing:recrystallization:softening 与传统铸锻高温合金相比,粉末高温合金具有 劳强度和损伤容限的设计,以Rene104(FGH98)、 晶粒细小、组织成分均匀、良好的力学性能和热加工 LSHR、RR1OO0等为代表的第三代粉末高温合金加 性能等优点,己逐渐成为先进军用及民用航空发动 入了Ta、Hf等合金元素,兼顾了高强度和优异的损 机涡轮盘的首选材料·-.目前国外己经历了三代 伤容限性能,己成功应用于国外航空产业中.国内 镍基粉末高温合金的研制和开发B-9:以Rene95 粉末高温合金研究自20世纪70年代后期起步,己 (FGH95)为代表的第一代粉末高温合金仅考虑高 成功研发了两代镍基粉末高温合金0-山,目前正在 的静强度,抗裂纹扩展能力和持久能力差,以 进行服役温度在750℃以上,具有高强度和高疲劳 René88DT(FGH96)和NI8等为代表的第二代粉末 裂纹扩展抗力的第三代新型镍基粉末高温合金的研 高温合金在调整合金成分和治金工艺方面注重了疲 制工作. 收稿日期:20130507 DOI:10.13374/j.issn1001-053x.2014.07.009:http:/journals.ustb.edu.cn第 36 卷 第 7 期 2014 年 7 月 北京科技大学学报 Journal of University of Science and Technology Beijing Vol. 36 No. 7 Jul. 2014 FGH98 合金的再结晶行为 李 昕,张麦仓,李 伟,董建新,郑 磊,姚志浩 北京科技大学材料科学与工程学院,北京 100083  通信作者,E-mail: mczhang@ ustb. edu. cn 摘 要 利用扫描电镜和透射电镜对热挤压态和退火态 FGH98 合金的相析出规律及组织特征进行了分析,并对其再结晶机 制进行了深入研究. 结果表明: 热挤压态 FGH98 合金在空冷过程中已经发生了少量的再结晶现象,随着挤压温度的提高,体 系内位错密度下降. 退火态 FGH98 合金中再结晶机制主要与体系内未回溶的一次 γ'相有关,在一次 γ'相聚集区再结晶主要 以依靠亚晶的聚合和亚晶的长大,或两者的混合机制进行形核; 随着一次 γ'相的减少,合金还可以通过应变诱发晶界迁移、多 晶粒交汇区形核、孪晶叠加等多种方式形核. 需要指出的是,FGH98 合金中未回溶的一次 γ'相在退火处理过程中也会通过部 分的回复和再结晶发生软化效应. 关键词 高温合金; 镍合金; 挤压; 退火; 再结晶; 软化 分类号 TG 146. 1 + 5 Recrystallization behaviors of FGH98 alloy LI Xin,ZHANG Mai-cang ,LI Wei,DONG Jian-xin,ZHENG Lei,YAO Zhi-hao School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China  Corresponding author,E-mail: mczhang@ ustb. edu. cn ABSTRACT The precipitated phase behavior,microstructure characteristics and static recrystallization mechanisms of FGH98 alloy in extruding and annealing states were systematically investigated by scanning electron microscopy ( SEM) and transmission electron microscopy ( TEM) . A portion of recrystallized grains were observed in as-extruded samples during the cooling process,and the dislo￾cation density decreases with the increasing of deformation temperature. The recrystallization mechanism of FGH98 alloy during the an￾nealing process is mainly dominated by residual primary γ' phase. In the region with a more content of residual primary γ' phase,static recrystallization is controlled by the coalescence and growth of subgrains; when residual primary γ' phase in the alloy decreases,many nucleation mechanisms of static recrystallization may occur,such as strain-induced boundary migration ( SIBM) ,nucleation in the juncture of several grains,and twins superposition nucleation. It must be pointed out that residual primary γ' phase in the alloy can al￾so be softened to somewhat extent by recovery and recrystallization during the annealing process. KEY WORDS superalloys; nickel alloys; extruding; annealing; recrystallization; softening 收稿日期: 2013--05--07 DOI: 10. 13374 /j. issn1001--053x. 2014. 07. 009; http: / /journals. ustb. edu. cn 与传统铸锻高温合金相比,粉末高温合金具有 晶粒细小、组织成分均匀、良好的力学性能和热加工 性能等优点,已逐渐成为先进军用及民用航空发动 机涡轮盘的首选材料[1 - 4]. 目前国外已经历了三代 镍基粉末高温合金的研制和开发[5 - 9]: 以 René95 ( FGH95) 为代表的第一代粉末高温合金仅考虑高 的静 强 度,抗裂纹扩展能力和持久能力差,以 René88DT ( FGH96) 和 N18 等为代表的第二代粉末 高温合金在调整合金成分和冶金工艺方面注重了疲 劳强度和损伤容限的设计,以 René104 ( FGH98) 、 LSHR、RR1000 等为代表的第三代粉末高温合金加 入了 Ta、Hf 等合金元素,兼顾了高强度和优异的损 伤容限性能,已成功应用于国外航空产业中. 国内 粉末高温合金研究自 20 世纪 70 年代后期起步,已 成功研发了两代镍基粉末高温合金[10 - 11],目前正在 进行服役温度在 750 ℃ 以上,具有高强度和高疲劳 裂纹扩展抗力的第三代新型镍基粉末高温合金的研 制工作.
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