在 Gleeble3500热力模拟试验机上对800H 合金进行高温单道次压缩实验,结合 OM和 TEM等表征手段,研究了该合金在变形温度1000~1150℃和应变速率0．01~1 s－1条件下的热变形行为.结果表明,动态再结晶行为更易发生在较低应变速率和高变形温度条件下,变形过程中动态再结晶形核机制主要包含晶粒碎化、晶界迁移及亚结构合并；考虑应变量因素,建立应变量耦合的双曲正弦本构方程,利用此模型预测合金的流变应力.本构模型预测值与实验测得值之间的线性关系达至0．99648,且平均相对误差仅2．019％,说明这种应变量耦合型本构方程能较好的预测800 H 合金在实验条件内的流变应力.
Hot compression tests of alloy 800H were carried out at deformation temperatures of 1 000-1 150 ℃and strain rates of 0.01-1 s-1 by Gleeble-3500 thermo-mechanical simulator.The evolution of microstructure were analyzed combined with the technique of OM,SEM and TEM.The experimental result shows that the dy-namic recrystallization (DRX)is more likely to occur at a low strain and high temperature,the DRX nucleation mechanisms of alloy 800 H mainly include grain fragmentation,grain boundary and substructure coalescence;a developed hyperbolic sine equation was established which take into account the effect of strain on constitutive e-quation,then the accuracy of the constitutive equation was verified.Compared with experimental results,the correlation coefficient and average relative error of predicted and measured values are 0.99648 and 2.019%,re-spectively,indicating that the developed equations can give an accurate estimate of the flow stress for alloy 800H.
参考文献
| [1] | 曹宇;邸洪双;张洁岑;张敬奇;马天军.800H合金动态再结晶行为研究[J].金属学报,2012(10):1175-1185. |
| [2] | 程晓农;王荣荣;李冬升;戴起勋;黄燕;刘瑜;陶亚平.800H合金的高温抗氧化性能[J].材料热处理学报,2012(6):95-99. |
| [3] | 赵晓东;陶乐晓;王金亮;陈慧琴;刘建生.新型高强铝合金的热变形行为及组织演变[J].稀有金属材料与工程,2014(9):2172-2176. |
| [4] | Ebrahimi, G.R.;Keshmiri, H.;Momeni, A.;Mazinani, M..Dynamic recrystallization behavior of a superaustenitic stainless steel containing 16%Cr and 25%Ni[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,201125/26(25/26):7488-7493. |
| [5] | Richard K.C. Nkhoma;Charles W. Siyasiya;Waldo E. Stumpf.Hot workability of AISI 321 and AISI 304 austenitic stainless steels[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2014:103-112. |
| [6] | A. Momeni;K. Dehghani;H. Keshmiri;G.R. Ebrahimi.Hot deformation behavior and microstructural evolution of a uperaustenitic stainless steel[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,20106(6):1605-1611. |
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