利用Gleeble-1500D热力模拟试验机，在变形温度为350—750℃、应变速率为0．01～5s^-1、总应变量约为0．5的条件下，对复合材料的高温热变形行为及动态再结晶临界条件进行研究。结果表明：弥散铜．WC复合材料高温流动应力·应变曲线主要以动态回复和动态再结晶软化机制为特征，峰值应力随变形温度的降低或应变速率的升高而增加；在真应力-应变曲线基础上，建立的Al2O3／Cu—WC复合材料高温变形本构模型较好地表征了其高温流变特性，其热激活能为208．35kJ／mol；同时，利用其θ-δ曲线出现拐点及-dθ／dδ曲线上出现最小值研究了动态再结晶的临界条件。
Hot deformation behavior and dynamic recrystallization critical conditions of Al2O3/Cu-WC composites were investigated by compression tests at 350-750 ℃ with the strain rate of 0.01 -5 s^-1 and total strain of 0.5 on a Gleeble-1500D simulator. The result shows that the Al2O3/Cu-WC composites exhibits the typical feature of the softening mechanism of dynamic recovery and dynamic recrystallization. The peak stress increases with the decreasing of deformation temperature or the increasing of strain rate. Based on the true stress-strain curves, the established constitutive equation characterizes the high-temperature flow behavior of Al2O3/Cu-WC composites quite well, and activation energy of the composites is about 208.35 kJ/mol. The critical conditions of dynamic recrystallization for the deformed Al2O3/Cu-WC composites are obtained based on the O-tr and dθ/dδ curves.
参考文献
| [1] | 黄树海,赵祖德,夏志新,蔡海艳,康凤,胡传凯,舒大禹.AZ80合金高温变形行为及加工图[J].稀有金属材料与工程,2010(05):848-852. |
| [2] | 曾卫东,周义刚,周军,俞汉清,张学敏,徐斌.加工图理论研究进展[J].稀有金属材料与工程,2006(05):673-677. |
| [3] | 李庆波,叶凡,周海涛,钟建伟,赵仲恺,王孟君.Mg-9Y-3Zn-0.5Zr合金的热变形行为[J].中国有色金属学报,2008(06):1012-1019. |
| [4] | 欧阳德来,鲁世强,黄旭,雷力明.TA15钛合金β区变形动态再结晶的临界条件[J].中国有色金属学报,2010(08):1539-1544. |
| [5] | 欧阳德来,鲁世强,崔霞,董显娟,吴超,邱伟.应用加工硬化率研究TA15钛合金β区变形的动态再结晶临界条件[J].航空材料学报,2010(02):17-23. |
| [6] | H. Mirzadeh;A. Najafizadeh .Prediction of the critical conditions for initiation of dynamic recrystallization[J].Materials & design,2010(3):1174-1179. |
| [7] | E. I. POLIAK;J. J. JONAS .Initiation of Dynamic Recrystallization in Constant Strain Rate Hot Deformation[J].ISIJ International,2003(5):684-691. |
| [8] | G. Gottstein;M. Frommert;M. Goerdeler;N. Schaefer .Prediction of the critical conditions for dynamic recrystallization in the austenitic steel 800H[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2004(0):604-608. |
| [9] | Sellars C M;Mctegart W J .On the mechanism of hot deformation[J].Acta Metallurgica,1966,14:1136-1138. |
| [10] | Sellars C M .Modelling microsmlctural development during hot rolling[J].Materials Science and Technology,1990,16(11):1072-1078. |
| [11] | C. Bruni;A. Forcellese;F. Gabrielli .Hot workability and models for flow stress of NIMONIC 115 Ni-base superalloy[J].Journal of Materials Processing Technology,2002(0):242-247. |
| [12] | Zener C;Hollomon J H .Effect of strain-rate upon the plastic flow of steel[J].Journal of Applied Physics,1944,15(01):22-27. |
| [13] | 胡赓祥;蔡殉;戎咏华.材料科学基础[M].上海:上海交通大学出版社,2010 |
| [14] | 毛卫民;赵新兵.金属的再结晶与晶粒长大[M].北京:冶金工业出版社,1994 |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%