磁化学合成Al_2O_3/7055Al复合材料的微观结构

摘要

Under pulsed magnetic field,7055 aluminum matrix composites reinforced by in-situ Al2O3 particles had been fabricated successfully from 7055 Al-Ce2（CO3）3 system.The results indicate that in-situ particles synthesized under pulsed magnetic field are finer and uniformly dispersed in the aluminum matrix.The range of round and Al2O3 particles size is 200-400nm.Compared with traditional in-situ reaction,the in situ reaction under pulsed magnetic field is faster and more complete,and shorten time considering the reactive kinetics.With the increasing of the plused magnetic intensity and applying time,the size and distribution of in-situ particles in the matrix become finer and more homogenous,the size is up to nanomete.%脉冲磁场下,以7055Al-Ce2（CO3）3为反应体系制备了内生Al2O3颗粒增强铝基复合材料。X射线衍射仪（XRD）、扫描电镜（SEM）、电子探针（EPMA）分析表明,在脉冲磁场作用下,原位合成的颗粒细小,呈球形或橄榄形的Al2O3颗粒尺寸为200～400nm,且弥散分布于基体中。从反应动力学角度进行考虑,与常规反应相比,磁场下反应更快更完全,并缩短了反应时间。随着脉冲磁场强度的增大,反应生成的增强颗粒变得更加细小,分布更均匀。当磁场作用的时间增加时,内生颗粒数目逐渐增多,尺寸逐渐细化,圆钝化,分布也变得均匀,颗粒达到纳米尺寸。