6061铝合金均匀化过程中AlMnSi弥散颗粒的析出尺寸对再结晶行为的影响

Effect of AlMnSi dispersion particle size on recrystallization of 6061 aluminum alloy during homogenization

利用力学性能测试、光学显微镜、扫描电镜、透射电镜和能谱分析技术等手段研究了均匀化过程中AlMnSi弥散颗粒的析出尺寸对6061铝合金再结晶行为的影响。结果表明:AlMnSi弥散颗粒在均匀化过程中沿着铝基体[001]晶带轴析出长大,晶体结构为体心立方结构。随着均匀化温度的升高,弥散颗粒的析出尺寸逐渐增大,当AlMnSi弥散颗粒平均尺寸由0.07μm增长到0.42μm,最大尺寸由0.21μm增大到1.12μm时,力学性能则是先升高后降低。6061铝合金T6态组织仍为变形组织;AlMnSi弥散颗粒尺寸增大到1.12μm,6061合金T6态组织中出现粗大再结晶,力学性能急剧降低。

Effect of the size of AlMnSi dispersion particles on recrystallization of 6061 aluminum alloy during homogenization was studied by using mechanical property test,OM,SEM,TEM and EDS techniques.The results show that the BBC type AlMnSi dispersion particles are precipitated and grown up along the [001] crystal axis of the aluminum matrix.With the increase of homogenization temperature,the precipitation size of dispersion particles is gradually increased.When the average size and the maximum size of AlMnSi dispersion particles respectively increasing from 0.07 μm to 0.42 μm and from 0.21 μm to 1.12 μm,the mechanical properties are increased first and then decreased correspondingly.At T6 state,the 6061 aluminum alloy is still of deformed structure.When the AlMnSi dispersion particle size is increased to 1.12 μm,coarse recrystallization microstructure appears in the alloy at T6 state,resulting that the mechanical properties are decreased sharply.