Comparative Analysis of Structure and Properties of Nb-B Inoculated Direct Chill Cast AA4032 Alloy Extruded from As-Cast and Homogenized Conditions

Abstract Al-Si wrought piston alloys can lack properties due to inefficient grain refining. A novel Al-Nb-B refiner was introduced some time ago, but has still not been assessed in industry for alloys. This paper describes the first trial of Al-Ni-B addition and its impact on full-scale manufacturing, structure, AA4032 products extruded with without billet homogenization. It is shown that Nb-B inoculation gives opportunities only have a refined as-cast structure also more homogenous distribution solute. In contrast, homogenization drives nucleation coarsening Mg 2 Si phase retained during further extrusion heat treatment affecting precipitation properties. observed non-homogenized specimens perform better machining tensile testing compared homogenized specimens. The results are supported by electron microscopy investigations microstructure formation different steps downstream processing.