High strength and toughness squeeze casting AlSi9MnMgCu alloy for automotive lightweighting
Year: 2026
Type: article
Abstract: AlSi10MnMg alloy is widely used in automotive die casting structure, yet the synergistic improvement of strength and toughness is still a core challenge for the application of this alloy. To address this issue, a novel high-strength and toughness AlSi9MnMgCu alloy was designed and fabricated via squeeze casting. The effects of T6 heat treatment on their microstructure and mechanical properties were investigated. The as-cast alloy consists of an α-Al matrix, eutectic Si phase, and three intermetallic compounds as α-Al 15 (Fe,Mn) 3 Si 2 , θ-Al 2 Cu, and Q-Al 5 Cu 2 Mg 8 Si 6 . It exhibited a tensile strength of 253 MPa, a yield strength of 137 MPa, and an elongation of 8.5%. After T6 heat treatment with solution at 530 °C for 3 h followed by aging at 180 °C for 4 h, the alloy achieved superior comprehensive mechanical properties with a tensile strength of 340 MPa, a yield strength of 255 MPa, and an elongation of 9.8%. TEM characterization revealed that the as-cast interwoven network-like Si phase fragmented gradually after solution treatment with discontinuous grain boundaries forming. Subsequent peak aging induced precipitation of abundant strengthening phases including short rod-like Q' and path-like θ'. The fragmentation of the network-like coarse Si phase, precipitation strengthening, and grain refinement synergistically enhanced both the strength and ductility of the AlSi9MnMgCu alloy.
Language: English
Subfield: Aerospace Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,640
OpenAlex ID: W7150709978