Microstructure of nanometer Al2O3 particles reinforced aluminum matrix composites processed by high pulsed electromagnetic field

The as-cast in situ Al2O3 particles reinforced aluminum matrix composites were subjected to the impact treatment due to the Lorentz force generated by high pulsed electromagnetic field. The magnetic induced intensity (B) was set as 1 T, 2 T and 3 T. Transmission electronic microscopy observation shows that the impact has induced the elastic deformation in materials that results in the enhancement of dislocation density. The value increases from 2.2×1011/m2 in as-cast sample to 8.9×1013/m2 in the 3 T treated one. Besides, stacking faults and deformation twins with 3, 4, 6 atomic planes can also be seen. The results demonstrate that high pulsed electromagnetic field is an efficient and economical approach to acquire a specific microstructure and, meanwhile, keep the original shape of sample.

► Al2O3p/Al composites will deform elastically when treated by HPEMF.
► HPEMF means high pulsed electromagnetic field with 1–3 T in the paper.
► The dislocation density will increase with the increase of B.
► In 3 T treated sample, stacking fault and deform twin can be seen.
► Meanwhile, the sample's shape does not been effected.