Because of their excellent properties in the as-cast condition, Al-MgMnSi alloys like Magsimal-59(tm) are being used increasingly for automotive applications. The preferred casting processes are 1) high pressure diecasting with vacuum or forcedventing systems or 2) squeeze-casting. Depending on casting application, a wide range of mechanical properties can be achieved They include high elongation (>14%) with medium yield strength or medium elongation with high yield strength (>200MPa). Forhigh-elongation requirements, a low-cost heat treatment has been developed that eliminates both solution heat treatment and water quenching, thereby also avoiding part distortion. Additionally, the influence of magnesium content on yield strength isdescribed. The paper also discusses results of scanning electron microscope (SEM) analysis and metallographic studies. Castings developed for automotive applications are shown.
展开▼
