The Effect of Solution Treatment on the Si Particles’ Morphology Evolution and the Thermal Conductivity and Tensile Properties of Sb-Modified Al-8Si-0.6Mg Alloys

The effects of solution treatment time on the morphology evolution Si particles and thermal conductivity tensile properties Sb-modified alloys were studied. results show that follows four mechanisms: spheroidization, necking splitting with large aspect ratios, fusion spherical particles, coarsening controlled by diffusion. first three mechanisms mainly occur at early stage treatment. addition Sb does not change law but it contribution various mechanisms, including promoting fusion, coalescence, as well significantly reducing rate, which makes modification more effective. increase in during is related to decrease anharmonicity lattice vibration, wave scattering, electron scattering particles. 0.4 wt. % alloy exhibits excellent strength elongation under as-cast T4- T6-heat-treated conditions, because reduces stress concentration delays germination propagation microcracks.