期刊文献+

GH864合金870℃高温时效过程中强化相的退变 被引量:7

Degradation of microstructure of GH864 superalloy during long exposure at 870 ℃
下载PDF
导出
摘要 利用光学显微镜、场发射SEM等手段,对标准热处理(1080℃×4 h/AC+845℃×24h/AC+760℃×16h/AC)后的GH864镍基合金分别在650℃和870℃进行长期时效,研究长期时效温度和时间对合金组织和性能的影响。结果表明,GH864合金在650℃时效1000 h过程中,随着时间的延长γ'相长大不明显,晶界碳化物及γ'相尺寸分布状态几乎保持不变,基体中有三次γ'相析出,随着时效时间延长硬度增加,体现了合金在该温度下良好的组织稳定性;在650℃及870℃长期时效,γ'相随温度升高及时间延长而粗化,其规律遵循L-S-W理论,且温度越高,粗化速率也越大,温度比时间的影响更为明显;在870℃温度时效3000 h过程中,γ'相急剧长大及其体积分数逐渐降低,γ'相时效后期的长大速率较初期减缓;同时,合金中的晶界碳化物逐渐溶解消失,局部位置γ'相完全溶入基体并导致复杂的合金元素反应,形成复杂组织,最终导致合金硬度下降,合金发生了明显退化。 Degradation behavior of microstructure of GH864 alloy after exposure at 650 ℃ and 870 ℃ for long to 3000 h were investigated by optical microscope and field emission SEM.The results show that γ′ strengthening phase and carbides at grain boundary of GH864 alloy exhibit no significant change during long exposure at 650 ℃,however,there are tertiary γ′ precipitates,and hardness of the alloy increases with the ageing time prolonging.Therefore,it indicates that microstructures of the alloy at 650 ℃ is much stable.Long exposure at 650 ℃ or 870 ℃,the coarsening rate of γ′ phase gradually increases with increasing temperature and time,and the coarsening behavior of γ′ phase meets the LSW aging theory.The growth rate of γ′ phase in the early stage is higher than that in the later stage,while the influence of temperature on the coarsening rate is more obvious than time.During aging at 870 ℃,the size of γ′ phase grows up sharply and the relative volume fraction of γ′ phase gradually decreases with aging time.Meanwhile,the carbides at grain boundary gradually dissolve and disappear.In local position,complex reaction occurrs by complete dissolution of γ′ phase,eventually leading to the decreases of hardness of GH864 alloy,which is suggested that the GH864 alloy is obviously degraded.
出处 《材料热处理学报》 EI CAS CSCD 北大核心 2011年第10期43-49,共7页 Transactions of Materials and Heat Treatment
基金 国家自然科学基金(51071017)
关键词 GH864合金 高温时效 显微组织 粗化速率 退化 GH864 super alloy long exposure at high temperature microstructure coarsening rate degradation
  • 引文网络
  • 相关文献

参考文献14

  • 1Chang K M, Liu X B. Effect of content on the mechanical behavior of the WASPALOY alloy system[ J]. Materials Sciences and Engineering A ,2001, 308:1 -8.
  • 2Semiatin S L,Fagln P N, Glavicic M G, et al. Deformation behavior of WASPALOY at hot-worklng temperatures [ J ]. Scripta Materialia, 2004,50: 625 - 629.
  • 3Liu X B,Bruce K, Chang K M. The effect of hold-time on fatigue crack growth behaviors of WASPALOY alloy at elevated temperature [ J]. Materials Science and Engineering A,2003,340:8 -14.
  • 4Penkalla H J,Wosik J,Czyrska F A. Quantitative microstructural characterization of Ni-base superalloy [ J ]. Materials Chemistry and Physics,2003, 81:417 -423.
  • 5姚志浩,董建新,张麦仓,郑磊.GH864合金显微组织与力学性能的关联性[J].稀有金属材料与工程,2010,39(9):1565-1570. 被引量:24
  • 6Brogdon M L, Rosenberger A H. Evaluation of the influence of grain structure on the fatigue variability of WASPALOY [ J ]. Superalloys 2008,2008 : 583 -588.
  • 7Rae C M F, Reed R C. The precipitation of topologically close-packed phases in rhenium-containing superalloys[ J]. Acta Materialia,2001,49 :4113 - 4125.
  • 8崔彤,王继杰,管仁国,陈礼清,赵光普.长期时效对GH4586B合金组织及高温拉伸性能的影响[J].材料热处理学报,2010,31(2):30-34. 被引量:8
  • 9Tokoro K, Wikstrom N P, Ojo O A, et al. Variation in diffusion-induced solidification rate of liquated Ni-Cr-B insert during TLP bonding of WASPALOY superalloy[ J ]. Materials Science and Engineering A ,2008,477:311 - 318.
  • 10姚志浩,洪成淼,董建新,张麦仓,郑磊.烟气轮机动叶片断裂原因分析[J].失效分析与预防,2008,3(4):23-27. 被引量:8

二级参考文献25

共引文献45

同被引文献58

引证文献7

二级引证文献50

;
使用帮助 返回顶部