A search for the eutectic system of high-temperature cast aluminium alloys

A quest for the eutectic system of novel cast aluminium alloys, having high-temperature capabilities, is critically assessed with two potential candidates of Al-Al3Ni and Al-Al11Ce3 examined and compared to the presently used Al-Si base. The conventionally cast Al-Al3Ni and Al-Al11Ce3 eutectics do not exhibit the anticipated advantage over Al-Si in strengthening retention at temperatures up to 500 degrees C. The promising differences between diffusivities of silicon, nickel, and especially cerium in aluminium, and eutectic melting temperatures, accompanied by high coarsening resistance of Al3Ni, Al11Ce3 phases and the eutectic hardness retention are inconsistent with observed similarities in the temperature-related strengthening-reduction of all three eutectics. These findings will help defining the criteria for development of the eutectic system, suitable for future heat-resistant aluminium alloys.

Automated summary

The research indicates that the novel cast aluminium eutectic systems of Al-Al3Ni and Al-Al11Ce3 do not show significant advantages over the traditional Al-Si base at high temperatures up to 500 degrees C. While there are differences in diffusivities of silicon, nickel, and cerium in aluminium, as well as eutectic melting temperatures and coarsening resistance of Al3Ni and Al11Ce3 phases, the observed similarities in temperature-related strengthening-reduction across all three eutectics highlight the need for further development criteria for heat-resistant aluminium alloys.