摘要
在250~400℃温度范围内以恒温、恒应变速率（10？3和10？2 s？1）对铸轧AZ31镁合金进行拉伸实验，在不同应变下研究温度和应变速率对动态再结晶的影响，探讨二相粒子对动态再结晶的影响，并分析动态再结晶机制。结果表明：当应变相同时，再结晶晶粒尺寸随温度升高而增大。中温区（200~300℃）动态再结晶的主导机制为连续动态再结晶，高温区（300℃以上）动态再结晶的主导机制为不连续动态再结晶。变形过程中破碎的Mg 17 Al 12相粒子及钉扎在晶界处的（Al,Mn）相粒子可提高动态再结晶的形核率。在350℃下，当应变速率由10？3 s？1升高到10？2 s？1时，晶粒尺寸逐渐减小，且出现孪生再结晶。
Tensile tests were conducted for a twin-roll cast AZ31 alloy under constant temperatures （250？400 ℃） and constant strain rates of 10？3 and 10？2 s？1, aimed to study the effects of temperature and strain rate on dynamic recrystallization at different strains, to explore the effects of the second phase particles on dynamic recrystallization, and to analyze the mechanisms of dynamic recrystallization. The results show that the grain size of the recrystallized grains increases with temperature under the same strain. The continuous dynamic recrystallization dominates at the intermediate temperature range （200？300 ℃）, while the discontinuous dynamic recrystallization dominates at high temperatures （over 300 ℃） . The fractured Mg17Al12 particles and the （Al, Mn） phase particles pinning at grain boundary can improve the nucleation rate of dynamic recrystallization. When the strain rate increases from 10？3 s？1 to 10？2 s？1 at 350 ℃, the grain size gradually decreases, and the twin recrystallizaiton occurs.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2013年第7期1796-1804,共9页
The Chinese Journal of Nonferrous Metals
基金
国家自然科学基金资助项目(50801034)
辽宁省高等学校杰出青年学者成长计划基金资助项目(LJQ2011026)
辽宁省十百千高端人才引进工程基金资助项目(2012207)
关键词
AZ31镁合金
铸轧
动态再结晶
AZ31 magnesium alloy
twin-roll cast
dynamic recrystallization
