研究抽拉速率对DZ483合金微观组织及力学性能的影响。结果表明：随着抽拉速率的提高，合金的一、二次枝晶间距逐渐减小，γ′相尺寸减小，但γ′相的数量增多；共晶组织及枝晶间碳化物的数量增多。碳化物形貌由块状转变成长条状，类型不随抽拉速率的提高而改变。随着抽拉速率的升高，除Cr元素偏析系数在1左右波动外，其余元素的偏析程度都增加，其中W、Mo元素偏析程度明显加重；DZ483合金的持久性能随抽拉速率的提高先升高后降低。不同抽拉速率下，合金断口均呈现出韧性断裂和脆性断裂混合特征，γ′相为合金的主要强化相。随着抽拉速率的提高，一方面，合金中γ′相的数量逐渐增多，尺寸逐渐减小，提高了合金的持久性能；另一方面，由于元素偏析程度加重、碳化物和共晶数量增多及γ′相筏形化规则程度的下降，降低了合金的持久性能。
The effects of withdrawal rate on the microstructure and mechanical properties of directionally solidified DZ483 superalloy were investigated. The results show that, with the withdrawal rate increasing, both the primary and secondary dendrite arm spacing decrease gradually, and the size ofγ′precipitates decreases, but the quantity ofγ′phase increases obviously. The number of eutectic and carbides within the interdendritic region increases. However, the morphology of carbides transforms from blocky into strip-like. Except the Cr element with segregation coefficient of about 1, the segregation of the elements becomes worse with the increase of the withdrawal rate, especially W and Mo. With the increase of the withdrawal rate, the stress rupture life of the alloy increases initially and then decreases. The main fractographic appearance is brittle and tough at different withdrawal rates. With the withdrawal rate increasing, on the one hand, the size ofγ′precipitates decreases, and the quantity increases, which improves the stress-rupture properties. On the other hand, stress-rupture properties of superalloy worsen because of the increase of element segregation, the increase of the number ofγ/γ′eutectic structure and carbides, and the decrease of the irregular morphology ofγ′rafting.
参考文献
| [1] | BRIDGMAN P W .Crystals and their manufacture,mass field[P].England,88650,1926-02-16. |
| [2] | 郭建亭.高温合金材料学(上册)[M].北京:科学出版社,2008:3-16. |
| [3] | POLLOCK T M;ARGON A S .Creep resistance of CMSX-3 nickel base superalloy single crystals[J].ACTA METALLURGICA ET MATERIALIA,1992,40(01):1-30. |
| [4] | 郭建亭,袁超,侯介山.高温合金的蠕变及疲劳-蠕变-环境交互作用规律和机理[J].中国有色金属学报,2011(03):487-504. |
| [5] | Sheng, L.Y.;Xie, Y.;Xi, T.F.;Guo, J.T.;Zheng, Y.F.;Ye, H.Q. .Microstructure characteristics and compressive properties of NiAl-based multiphase alloy during heat treatments[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2011(29/30):8324-8331. |
| [6] | FU H Z;GENG X G .High rate directional solidification and its application to single crystal superalloys[J].SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS,2001,2(01):197-204. |
| [7] | Jian ZHANG,Langhong LOU.Directional Solidification Assisted by Liquid Metal Cooling[J].材料科学技术学报（英文版）,2007(03):289-300. |
| [8] | HARRIS K;ERICKSON G L;SCHWER R E.Directionally solidified and single-crystal superalloys-Metals Handbook[M].New York:American Society for Metals,1990:995-1010. |
| [9] | 金涛,李金国,赵乃仁,王震,孙晓峰,管恒荣,胡壮麒.抽拉速率对一种镍基单晶高温合金凝固参数和凝固组织的影响[J].材料工程,2002(03):36-39,48. |
| [10] | 赵乃仁,金涛,孙晓峰,管恒荣,杨洪才,胡壮麒.抽拉速率对SRR99单晶高温合金组织和性能的影响[J].材料研究学报,2008(01):46-52. |
| [11] | 刘忠元;李建国;傅恒志 .凝固速率对定向凝固合金DZ22技晶臂间距和枝晶偏析的影响[J].金属学报,1995,3l(07):329-332. |
| [12] | 冯广召,沈军,邹敏佳,刘林.抽拉速度对高温合金DZ125定向凝固中缩松的影响[J].铸造,2009(05):427-430. |
| [13] | L.Y. Sheng;J.T. Guo;Y.X. Tian .Microstructure and mechanical properties of rapidly solidified NiAl-Cr(Mo) eutectic alloy doped with trace Dy[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2009(1/2):730-734. |
| [14] | 张剑,骆宇时,赵云松,杨帅,贾玉亮,崔丽丽,许剑伟,唐定中.一种低密度镍基单晶高温合金的组织与性能研究[J].航空材料学报,2011(z1):90-93. |
| [15] | 顾林喻,刘忠元,史正兴.高梯度快速定向凝固下DZ22高温合金的显微偏析[J].中国有色金属学报,1996(02):110-113. |
| [16] | J. S. Hou;J. T. Guo;L. Z. Zhou;H. Q. Ye .Sigma phase formation and its effect on mechanical properties in the corrosion-resistant superalloy K44[J].Zeitschrift fur Metallkunde,2006(2):174-181. |
| [17] | POLLOCK T M;ARGON A S .Directional coarsening in nickel-base single crystals with high volume fractions of coherent precipitates[J].Acta Metallurgical Materials,1994,42:1859-1874. |
| [18] | J.S. Hou;J.T. Guo;L.Z. Zhou .Microstructure and mechanical properties of cast Ni-base superalloy K44[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2004(1/2):327-334. |
| [19] | SCHNEIDER W;MUGHRABI H.Creep and fracture of engineering materials and structures[A].London:Swansea,1993:209-213. |
| [20] | Yu Jinjiang;Sun Xiaofeng;Jin Tao;Zhao Nairen;Guan Hengrong;Hu Zhuangqi .Effect of Re on deformation and slip systems of a Ni base single-crystal superalloy[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2007(1/2):39-43. |
| [21] | BETTGE D;OSTERLE W;ZIEBS J .Temperature dependenceof yield strength and elongation of the nickel-base superalloy IN738LC and the corresponding microstructural evolution[J].Materials Research and Advanced Techniques,1995,86:190-197. |
| [22] | 夏鹏成,于金江,孙晓峰,管恒荣,胡壮麒.高温时效时间对定向凝固DZ951镍基高温合金组织和持久性能的影响[J].稀有金属材料与工程,2010(01):69-71. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%