The influence of modification and squeeze casting on properties of AlSi11 alloy castings

The results of structural examinations and tests of mechanical properties of AlSi11 alloy, either gravity or squeeze cast, have been presented. The investigations have been carried out for both the non-modified silumin and the alloy modified with AlSr10 strontium master alloy. The measurements have been carried out for the cast plates of dimensions 200x100x25 mm. It has been found out that the modification combined with squeeze casting provides an advantageous set of strength and plastic properties [...]. The metallographic examination has revealed a significant refinement of both the primary \alfa-phase dendrites and the silicon eutectics, however being dependent on the method of modification and casting. It has been found that the refinement of the primary crystals results from the influence of external pressure exerted on the solidifying casting, while the refinement observed for silicon eutectics is an effect of combined influence of modification and squeeze casting.