湖南大学学报（自然科学版）2017，Vol.44Issue(12)：14-19,149,7.DOI:10.16339/j.cnki.hdxbzkb.2017.12.003
挤压温度对Mg-3Zn-2.5Al-2.5Ca合金的微观组织和力学性能的影响
Influence of Extrusion Temperature on Microstructure and Mechanical Properties of Mg-3Zn-2 .5Al-2 .5 Ca Alloy
摘要
Abstract
The effect of extrusion temperatures on the microstructures and mechanical properties of Mg-3Zn-2 .5Al-2 .5Ca(ZAC333) alloy was investigated by metallograph ,SEM ,XRD and tensile tests .The results show that the average grain size of the as-cast alloy is 185 μm .Due to the dynamic recrystallization , the grain size of as-extruded alloys was reduced from 6 .32 μm to 3 .36 μm with the extrusion temperature decreasing from 623 K to 523 K .The second phase of semi-continuous Al2 Ca and continuous Ca2 Mg6 Zn3 was broken ,which distributed along the grain boundary in the as-cast ZAC333 alloy .Compared with as-cast alloy ,the mechanical properties of as-extruded ZAC333 alloy were improved .The tensile and yield strength of as-extruded alloy increased from 176 to 292 M Pa ,264 to 334 M Pa ,respectively ,while elongation decreased from 20％ to 9％ .The improvement of mechanical properties for ZAC333 alloy can be attributed to the couple effects of refined crystalline strengthening caused by dynamic recrystallization and dispersion strengthening for the refined second phases during hot extrusion .关键词
ZAC333合金/挤压温度/动态再结晶/第二相/力学性能Key words
ZAC333 alloy/extrusion temperature/dynamic recrystallization/the second phase/me-chanical properties分类
矿业与冶金引用本文复制引用
陈鼎,章凯,董鹏,陈振华..挤压温度对Mg-3Zn-2.5Al-2.5Ca合金的微观组织和力学性能的影响[J].湖南大学学报（自然科学版）,2017,44(12):14-19,149,7.基金项目
美国波音公司合作项目(2015-SDB-127) （2015-SDB-127）
