An assessment of the effect of process history on the structure and mechanical properties of hypereutectic silumins

An effect of process history of manufacturing the AlSi17Cu3Mg1.5Ni1,5 alloy on its tensile strenght R_m hardness HB, and elongation A_5 was investigated. The individual elements of process history of the alloy fabrication included: type mould (sand or metal mould), modification process, and type of heat treatment (solutioning and ageing). Basing on a multivariance MANOVA test, it was possible to determine not only the effect of the main parameters, like foundry mould type, modification and heat treatment, but also an interaction of these effects. Consequently it has been concluded that the tensile strenght R_m of the examined alloy is statistically most affected by the process of modification, followed by the type of the applied heat treatment, and the type of foundry mould (metal mould). The strongest interactive effect on the value of R_m had a combination of the process and heat treatment.