In this study, the tensile properties of unmodified A356 alloys with trace additions of Ni or V were investigated. The nominal concentrations of these elements were set at 600 and 1000 ppm, respectively. Specimens obtained from sand and permanent mould casting in as-cast and T6 heat treated conditions were examined. It was found that the precipitation of Ni-rich intermetallics strongly influences the tensile properties of the sand cast A356 alloy in as-cast condition, leading to a reduction of both the yield strength (Rp0.2) and ultimate tensile strength (UTS) by 87% and 37%, respectively. Conversely, the V addition increased Rp0.2 and UTS by 42% and 25% due to a solid solution strengthening effect. After T6 heat treatment, the sand cast A356 alloys containing V exhibited slightly higher mechanical properties as compared to the A356 reference alloy (about 18%), whereas the detrimental effect of Ni was eliminated. The cooling rate became the main parameter influencing the mechanical properties of permanent mould cast alloys: no significant differences in mechanical properties were observed between the reference alloy and Ni- or V-containing alloys in both as-cast and T6 conditions.

The effect of Ni and V trace elements on the mechanical properties of A356 aluminium foundry alloy in as cast and T6 heat treated conditions

CASARI, Daniele;MERLIN, Mattia;GARAGNANI, Gian Luca
2014

Abstract

In this study, the tensile properties of unmodified A356 alloys with trace additions of Ni or V were investigated. The nominal concentrations of these elements were set at 600 and 1000 ppm, respectively. Specimens obtained from sand and permanent mould casting in as-cast and T6 heat treated conditions were examined. It was found that the precipitation of Ni-rich intermetallics strongly influences the tensile properties of the sand cast A356 alloy in as-cast condition, leading to a reduction of both the yield strength (Rp0.2) and ultimate tensile strength (UTS) by 87% and 37%, respectively. Conversely, the V addition increased Rp0.2 and UTS by 42% and 25% due to a solid solution strengthening effect. After T6 heat treatment, the sand cast A356 alloys containing V exhibited slightly higher mechanical properties as compared to the A356 reference alloy (about 18%), whereas the detrimental effect of Ni was eliminated. The cooling rate became the main parameter influencing the mechanical properties of permanent mould cast alloys: no significant differences in mechanical properties were observed between the reference alloy and Ni- or V-containing alloys in both as-cast and T6 conditions.
2014
Casari, Daniele; T. H., Ludwig; Merlin, Mattia; L., Arnberg; Garagnani, Gian Luca
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11392/1990412
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 67
  • ???jsp.display-item.citation.isi??? 52
social impact