Advancements in microstructure, texture characterization, and mechanical properties of powder metallurgy Al-Si-Mg-Fe alloy for engineering applications

Abstract

Metal powder metallurgy (PM) is widely utilized in the tool and automotive industries due to its near-net forming advantages. While PM aluminum alloys have been explored in numerous studies, their practical engineering applications are still limited. Thus, this research delves into the nuanced aspects of PM Al-Si-Mg-Fe alloy. By employing hot-rolled dynamic recrystallization to control the metallurgical texture and introducing T6 treatment to refine the microstructure. These optimizations aim to enhance the properties of PM aluminum alloy materials. Results revealed that grain coarsening in the PM Al-Si-Mg-Fe alloy hampers the grain boundary strengthening effects, thus limiting the strength. Moreover, the solid-solution treatment applied to the PM specimens efficiently disperses silicon particles within the matrix, preventing the aggregation of silicon particles and the associated brittle effect caused by interface peeling. By implementing a three-stage process, sintering-rolling-T6 treatment, the rolled-T6 exhibited impressive tensile strength (291 MPa) and ductility (17 %), highlighting the excellent engineering applicability of PM Al-alloys. TEM analysis confirmed the presence of nanoprecipitation Al3Mg and Al9Fe2 hard components within the matrix, contributing to the strength enhancement. These findings not only represent a significant milestone in the advancement but also provide valuable references for engineering applications in the field of PM Al-alloys.