Research Status of Alloy Elements in Aluminum Alloy for Automobile Structure Parts Castings

Author of the article:ZHANG Haitao, HE Hao, YIN Gang, GUO Kaimin, BAI Jie

Author's Workplace：Key Lab of Electromagnetic Processing of Materials, Ministry of Education, Northeastern University, Shenyang 110819, China

Key Words：alloy elements; automobile structural parts; Al Si cast aluminum alloy; Al Mg cast aluminum alloy

Abstract：The cast aluminum alloys commonly used in automobile structural parts were mainly divided into Al-Si and Al-Mg systems. The common methods of adding alloying elements to improve the properties of alloys were reviewed. For Al-Si cast aluminum alloy, Si can not only improve the casting property, but also inhibit the formation of needle-like Al5FeSi phase. Mg and Cu were the main strengthening elements, which can form Mg2Si phase, Al2Cu phase and Q-Al5Cu2Mg8Si6 phase. Mn and Mo mainly inhibited the formation of acicular iron-rich phase. V, Ti and Zr can refine the grain and improve the mechanical properties. For Al-Mg cast aluminum alloys, when Si content is high, such as MagSimal 誖-Plus (AlMg6Si2MnZr) alloy, Mg2Si phase was the main strengthening phase, in order to avoid the formation of acicular iron-rich phase, Fe content was very low. When Fe content was high, such as Castaduct誖-42 (AlMg4Fe2) alloy, it mainly relies on Mg element solid solution in Al matrix, and forms Al-Fe eutectic phase to improve the alloy strength. Si element was impurity element, which can reduce the formation of acicular Al-Fe-Si phase.