对GH864合金进行3种固溶温度：1040、1060、1080℃×4 h/AC＋双时效（845℃×24 h/AC＋760℃×16 h/AC）热处理,并对其组织和力学性能进行了研究。结果表明：随着固溶温度的提高,晶粒尺寸出现明显长大,但增长速率越来越小,碳化物连续均匀分布在晶界上,同时,均匀的γ＇强化相在基体上弥散析出;在合金性能上,随着固溶温度的提高,合金的高温拉伸伸长率、断面收缩率及室温冲击韧性都逐渐下降;然而,合金的高温815℃抗拉强度基本不变,其高温屈服强度及室温硬度经过1060℃固溶后出现峰值,同时合金的815℃/325 MPa持久性能及高温裂纹扩展速率在该固溶温度下表现出最佳的性能。综合该合金强度和塑性的最佳匹配,确定了GH864合金叶片热处理的最佳固溶温度及时效处理控制工艺为：1060℃×4 h/AC＋845℃×24h/AC＋760℃×16 h/AC。
Microstructure and properties of GH864 alloy for gas turbine blade solution-treated at 1040,1060,1080 ℃ for 4 h air cooling,and then double-aged at 845 ℃ for 24 h and 760 ℃ for 16 h were studied.The results indicate that grain size grow up significantly for the alloy solution-treated at 1040 ℃ and its growth rate become slow with further increasing solution temperature.Uniform carbides at grain boundaries and γ′ phases precipitated in the matrix are observed and no obvious change is found after solution treatment.Elongation,reduction of area at 815 ℃ and impact toughness at room temperature of the alloy decrease gradually as solution temperature increases.However,at high temperature,tensile strength of the alloy is almost the same with that at room temperature,while its elevated temperature yield strength,life of stress rupture and hardness at room temperature present peak values after solution treatment at 1060 ℃.Meanwhile,stress rupture properties at 815 ℃/325 MPa and fatigue crack growth rate at 650 ℃ exhibit best performance after solution treatment at 1060 ℃.Based on the experiments,the solution treatment process of GH864 alloy blade is recommended：1060 ℃×4 h/AC＋845 ℃×24 h/AC＋760 ℃×16 h/AC.
参考文献
| [1] | Kelekanjeri V;Siva Kumar G;Gerhardt Rosario A .Characterization of microstructure fluctuations in Waspaloy exposed to 760 ℃ for times up to 2500h[J].Electrochimica Acta,2006,51:1873-1880. |
| [2] | Mandy L Brogdon;Andrew H Rosenberger.Evaluation of the influence of grain structure on the fatigue variablity of waspaloy[A].TMS,Warrcndale,PA,2008:583-588. |
| [3] | K. Tokoro;N.P. Wikstrom;O.A. Ojo .Variation in diffusion-induced solidification rate of liquated Ni-Cr-B insert during TLP bonding of Waspaloy superalloy[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2008(1/2):311-318. |
| [4] | Chang Keh-minn;Liu Xingbo .Effect of γ' content on the mechanical behavior of the Waspaloy alloy system[J].Materials Science and Engineering A:Structural Materials Properties Microstructure and Processing,2001,308:1-8. |
| [5] | Liu XB.;Kang B.;Chang KM. .The effect of hold-time on fatigue crack growth behaviors of WASPALOY alloy at elevated temperature[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2003(1/2):8-14. |
| [6] | Martin Goetting;Joachim Roesier .A finite element creep crack growth model for Waspaloy[J].Computers & structures,2007(3/4):225-232. |
| [7] | 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(09):1565-1570. |
| [8] | G. LVOV;V.I. LEVIT;M.J. KAUFMAN .Mechanism of Primary MC Carbide Decomposition in Ni-Base Superalloys[J].Metallurgical and Materials Transactions, A. Physical Metallurgy and Materials Science,2004(6):1669-1679. |
| [9] | Hoffelner W;Scalin R B .On the correlation of microstructure,fatigue life and fatigue crack propagation in nickel base superalloys[J].Engineering Materials Advisory Services,1984,3:1647-1658. |
| [10] | 才庆魁.金属疲劳断裂理论[M].沈阳:东北工学院出版社,1989 |
| [11] | Bartos J;Antolovich S D.The effects of grain size and γ' size on fatigue crack propagation in Rene 95[A].Waterloo,Ontario,Canada,1977:995-1005. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%