Forging of an age-hardenable Mg–Al–Ca–Mn–Zn alloy on industrial scale

Abstract

Weight reduction plays an important role in transportation industries, directly impacting on fuel consumption and vehicle range. The use of multi-material mixes is common practice, allowing for an optimum application of specific material properties. Light metals, primarily aluminum alloys, are used in both, cast and wrought state, to good effect. On the other hand, magnesium alloys, which are still lighter by one third, are used in castings exclusively. While scientific research and development on Mg wrought alloys is progressing steadily, industrial implementation is still scarce. As a result, safety relevant and structural applications made from Mg wrought products are nearly nonexistent. To increase acceptance and facilitate industrial application for this interesting class of materials we investigated the forging process of an original-sized automotive control arm. To ease industrial access, the used age hardenable Mg–Al–Ca–Zn–Mn lean alloy, can be processed similarly to Al alloys, e.g. 6xxx series. This work describes the development sequence, starting with the analysis of the forming window, followed by laboratory forging trials and industrial sized part production, providing information on forming characteristics as well as possible difficulties.