Research On The Preparation And Characterization Of Al₂O₃/Fe₃Si Nano-Composite Powders

In this work,using QM-3SP2 planetary ball mill,Al₂O₃/Fe₃Si nano-compositepowders were prepared by the method of mechanochemistry with Fe₃O₄,Fe₂O₃,Al andSi mixed powders as raw materials.The composite powders were investigated byXRD,TEM,SEM and DSC-TG method.The reseach results indicated that:1. Al-Fe₂O₃-Si mixed powders reacted after milled for 5h,and Al₂O₃/Fe₃Si compositepowders were obtained by milling of Al-Fe₂O₃-Si mixed powders for 20h. Al-Fe₃O₄-Si mixed powders reacted after milled for 1h,and Al₂O₃/Fe₃Si composite powderswere obtained by milling of Al-Fe₃O₄-Si mixed powders for 5h.2. The average crystallite dimension of production decreased with milling time.Itdecreased very fast at the intial stage of ball milling.Then the rate of declinegradually slowed down.After miling for 20h,The average crystallite dimension ofFe₃Si and Al₂O₃ prepared with Al-Fe₂O₃-Si is 13.6nm and 19.7nm respectively,andthe average crystallite dimension of Fe₃Si and Al₂O₃ prepared with Al-Fe₃O₄-Si is19.5nm and 26.0nm respectively.3. The composite powders were annealed after milled for 5h,10h and 20h with Al-Fe₂O₃-Si mixed powders.The Phase of composite powders did not change.Thediffraction peak of each phase became more perfect.4. After miling for 20h,Al₂O₃/Fe₃Si nano-composite powders can be synthetized withtwo sets of sample(Al-Fe₂O₃-Si mixed powders and Al-Fe₃O₄-Si mixed powders).The prepared compound possess Nanocrystalline structure. The sizes of compoundparticle are very small. And most of the compound particle are submicron particle.The shape of compound particle is regular,and most of the compound particle isspherical fairly.In sum,Al₂O₃/Fe₃Si nano-composite powders can be synthetized by the method ofmechanochemistry quickly and simply.This work provided an experimental basis forthe preparation of Al₂O₃/Fe₃Si nanocomposites.