The　effect　of　Al2O3　on　the　diffusion　behavior　of　Fe　impurity　in　aluminum　melts　was　analyzed　by　molecular　dynamics　simulation　methods　in　terms　of　mean　square　displacement　(DMS),　self-diffusion　coefficient　(D),　radial　distribution　function　(g(r))　and　coordination　number　(Nij).　The　simulation　results　show　that　Al2O3　is　the　key　factor　affecting　the　diffusion　and　enrichment　of　Fe.　With　the　increase　of　Al2O3　content,　the　DMS　of　Fe　decreases　and　this　trend　increases　as　the　time　prolongs,　resulting　in　a　decrease　of　the　diffusion　coefficient　from　0.173×10-8　m2/s　to　0.037×10-8　m2/s.　Therefore,　Al2O3　in　aluminum　melt　hinders　the　diffusion　of　Fe,　and　the　tendency　increases　with　the　extension　of　time.　Meanwhile,　with　the　increase　of　Al2O3　content,　the　g(r)　curve　changes　significantly,　the　height　of　the　first　peak　of　the　curve　gradually　becomes　higher　and　the　Nij　of　Fe　atoms　increases,　finally　results　in　the　enrichment　of　Fe.　The　analysis　shows　that　Al2O3　destroys　the　ordered　arrangement　of　atoms　in　aluminum　melt,　changes　the　distortion　energy　of　Fe　and　the　viscosity　of　melt,　leading　to　the　decline　in　diffusion　capacity　and　enrichment　intensification　in　enrichment　of　Fe,　which　creates　favorable　conditions　for　the　formation　of　Fe-rich　phase.　The　Fe　impurity　often　exists　around　Al2O3　in　the　form　of　Fe-rich　phase,　further　confirming　that　Al2O3　can　be　used　as　a　heterogeneous　substrate　to　promote　the　nucleation　and　growth　of　Fe-rich　phase.　To　sum　up,　Fe　impurity　is　directly　related　to　the　Al2O3　content,　the　decrease　of　Al2O3　content　is　beneficial　to　reduce　the　enrichment　tendency　of　Fe　and　reduces　the　forming　possibility　of　Fe-rich　phase.　This　is　consistent　with　the　results　of　molecular　dynamics　simulation,which　shows　that　the　simulation　method　is　feasible.　©　2023　Central　South　University　of　Technology.　All　rights　reserved.