High as-cast strength die-cast AlSi9Cu2Mg alloy prepared by nanoparticle strengthening with industrially acceptable ductility

Abstract High as-cast strength die-cast AlSi9Cu2Mg alloy was achieved with industrially acceptable ductility, via the addition of titanium diboride nanoparticles. The main intermetallic compounds in were identified as θ–Al2Cu and Q–Al5Cu2Mg8Si6 phases. Fe-rich compound formed present a high Mn/Fe ratio 3:1 determined BCC structured α–Al15(Fe,Mn)3Si2 phase lattice parameter a = 1.2702 nm, had highly faceted morphology {110} surface termination. Al matrix refined by ∼65% from 18.1 μm to 6.4 μm, after adding 3.0 wt% nanoparticles showed coherent interface matrix, (11-1) face parallel (0001) diboride. containing exhibited yield 233 ± 3 MPa tensile 398 ± 7 MPa, well elongation 4.8 ± 0.7%, it at least 23% improvement over existing alloys. strengthening nanoparticle (∼32 MPa) higher than that refining (∼10 MPa). also affected fracture alloy, cracks prone form Q compounds,