Magnesium Engine Cradle - The USCAR Structural Cast Magnesium Development Project 2005-01-0337

The Structural Cast Magnesium Development Project is a jointly sponsored effort by the US Department of Energy (DOE) and the US Council for Automotive Research (USCAR) Automotive Metals Division (AMD) to identify and resolve technical and manufacturing issues that limit the light weighting opportunities of applying large-scale structural cast magnesium automotive components. This project, which began in the end of year 2001, comprises General Motors, Ford, DaimlerChrysler and thirty-four other North America companies and organizations. The project has its overall objective set to determine the technical feasibility and practicality of producing and implementing a one-piece front engine cradle casting. This paper provides an overview of the project scopes and up-to-date accomplishments. The engine cradle design criteria are introduced in various aspects including magnesium alloys property database development, component design and analysis, corrosion protection and coating strategy, assembly constraints, crashworthiness assessments, noise vibration harshness performance, and durability. To assess its manufacturability of the engine cradle, a large-scale structural cast, the project adopts two casting processes, i.e. high pressure die cast and low pressure permanent mold. With the support of science and technology, the project activities also focus on developing “tools”, 1) numerical simulation model that predicts mold cavity fill and casting solidification, 2) material simulation models that predict cast component monotonic and cyclic properties, and 3) non-destructive evaluation equipment, procedures and process sensors. The ultimate goals of the project are to enhance the casting processes and large-scale structural automotive products, and to promote the magnesium infrastructure in North America.