Unified casting (UniCast) aluminum alloy-a sustainable and low-carbon materials solution for vehicle lightweighting

1.Background The wave of applying aluminum(Al)in the production of in-ternal combustion engine vehicle((ICEV)was initiated since 1970s[1],mainly driven by the pursuit of energy and environmental sus-tainability,i.e.,improving fuel economy and reducing greenhouse gas(GHG)emission[2-4].Al alloys have advantages over steel not only in density(～2.7 g/cm3,about one third of steel's),but also in thermal conductivity and corrosion resistance.Another notable ad-vantage of Al is that it can be tailored to become very castable for a wide range of shape casting techniques via alloying methodology[5].Al-Si type casting alloys are thus far the workhorse in the Al casting industry[6-8].They account for nearly 70％of total mass of Al applied in passenger vehicles and show very high penetration in the manufacturing of road wheels,steering knuckles,engine blocks and transmission cases[9].