Al3Zr析出相对Al-Zn-Mg-Cu合金板组织、织构与性能的影响

采用不同均匀化制度获得了Al3Zr粒子在晶界析出状态存在显著差异的两种Al-7.81Zn-1.62Mg-1.81Cu(7085型)合金铸锭试样,研究两种铸锭试样热轧板的微结构、织构和性能。结果表明:分级均匀化可促进Al3Zr粒子在晶界区域的析出;均匀化过程中Al3Zr粒子晶界析出量越少,热轧后轧制形变织构组分越强;与基体共格的Al3Zr粒子既能阻碍基于应力作用的位错运动,使轧制形变织构减弱,又能阻碍亚晶界/晶界的热激活运动,影响热轧过程中的动(静)态回复和再结晶,提高材料时效后的硬度,延长峰值硬度存在时间,从而提高材料的力学性能。

Effects of precipitation of Al3Zr particles on microstructures,textures and properties of Al-Zn-Mg-Cu alloy hot-rolled plate

The precipitation of Al3Zr particles near grain boundary was significantly different after two kinds of homogenization in the experimental Al-7.81Zn-1.62Mg-1.81Cu(AA7085) alloy.The microstructures,textures and properties of these two specimens were investigated.The results show that staged homogenization can promote Al3Zr particles precipitate in grain boundary areas.The less the Al3Zr particles precipitate in the grain boundary areas,the stronger the hot-rolling textures are.Al3Zr particles which are coherent with matrix would inhibit the movement of dislocation induced by stress and also the migration of sub-grain boundary and grain boundary induced by thermal activation.In this way,Al3Zr particles could decrease the deformation textures and prevent recovery and recrystallization,which improves its hardness and extends the existence time of peak hardness.All these improve mechanical properties of materials.