Microstructure and mechanical properties of Al–Si cast alloy with additions of Zr–V–Ti

• Al(ZrTiV)Si phases were found in the studied Al–Si alloy with Zr–V–Ti additions.
• The studied alloy achieved up to 40% higher strength up to 200 °C temperature.
• Also, the studied alloy was ∼5 times higher ductile than A380.

The microstructure and tensile properties at temperatures up to 300 °C of an experimental Al–7Si–1Cu–0.5Mg (wt.%) cast alloy with additions of Ti, V and Zr were assessed and compared with those of the commercial A380 grade. The microstructure of both alloys consisted of Al dendrites surrounded by Al–Si eutectic containing, within its structure, the ternary Al–Al2Cu–Si phase. Whereas the Al15(FeCrMn)3Si2 phases were present in the A380 alloy, Ti/Zr/V together with Al and Si phases, Al(ZrTiV)Si, were identified in the experimental alloy. As a result of chemistry modification the experimental alloy achieved from 20% to 40% higher strength and from 1.5 to 5 times higher ductility than the A380 reference grade. The role of chemistry in improving the alloy thermal stability is discussed.

Figure optionsDownload as PowerPoint slide