SILAFONT-36, THE LOW IRON DUCTILE DIE CASTING ALLOY DEVELOPMENT AND APPLICATIONS

Abstract

Silafont®-36 (AlSi9MgMn) was the first successful application of a low iron die-casting alloy for the automotive market. Key elements concerning the alloy development beside silicon and the modifying strontium are manganese, which avoids sticking to the die and forms globulitic intermetallic phases that provide high ductility, and magnesium, which determines the yield strength and ultimate tensile strength of the alloy. Optimum limits for manganese providing high ductility and good ejection behaviour were studied. Mechanical properties as a function of magnesium were shown with focus on very low magnesium content, which resulted in an alloy without any long-term aging behaviour. This paper presents the main features of the alloy, providing an overview on the new casting applications for the automotive sector.