摘要
在Gleeble-3500热模拟机上对SiCp／7A04铝基复合材料在应变速率为0．001～1s^-1、变形温度为300～450℃条件下的流变行为进行了研究．结果表明：在实验范围内，SiCp／7A04铝基复合材料热压缩变形时均存在较明显的稳态流变特征；真应力随温度升高而降低，随应变速率的增加而升高；金相组织观察表明，动态再结晶是SiCp／7A04复合材料软化的一个重要机制，变形温度越高，动态再结晶越充分；应变速率越大，再结晶晶粒就越小．可以用包含Arrhenius项的Z参数描述SiCp／7A04复合材料高温变形时的流变行为，其中变形激活能Q=159．87kJ／mol．
The deformation behavior of SiCp/7A04 was studied in the temperature range from 300-450℃ and the strain rate from 0. 001-1 s^-1 on the Gleeble-3500 hot simulator. The results show that the steadystate flow characteristics exist during the hot compression deformation of the composite. The true stress values increase with increasing of strain rate or decreasing of temperatures. The optical microstructures show that the dynamic recrystallization is an important softening mechanism for the composite. The dynamic recrystallization happens more completely with the increase of temperatures, and the higher the strain rates the smaller the recrystallized grains. The deformation behavior of SiCp/7A04 composites during high temperatures can be represented by a Zener-hollomon parameter in the hyperbolic Arrhenius-type equation, and the deformation activation energy Q is 159.87 kJ/mol.
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2008年第9期1405-1409,共5页
Journal of Shanghai Jiaotong University
基金
上海市科委重点攻关项目(075211012)
关键词
铝基复合材料
高温变形
流变应力
热模拟
aluminum matrix composite
high temperature deformation
flow stress
hot simulator
