Microstructure evolution and properties of nanoparticulate SiC modified AlSi10Mg alloys

In this work, novel AlSi10Mg composites modified by SiC nanoparticles have been successfully produced by a combined route including solvent-assisted dispersion, low-energy planetary ball milling and selective laser melting. The effect of laser-energy-input (E-V) on the microstructure evolution and mechanical properties of the composites was systematically studied. The results showed that the hardly dissolved or reacted SiC nanoparticles tended to be distributed at the cell boundaries, significantly refining the matrix grains by the promotion of heterogeneous nucleation process and the Zener pinning effect. However, the weak metallurgical bonding and the formation of Al4C3 phase caused a detrimental impact to tensile properties. On the contrary, the consumption of SiC nanoparticles at higher E-V significantly enhanced the strength and elongation to fracture of the composites through the homogenization of microstructure, better metallurgical bonding, and the joint action of SiC/Al4SiC4/Al interface. Specifically, the AlSi10Mg/SiC composite prepared at 210 W presented excellent mechanical performance (131.7 HV0.1 for hardness, 101 GPa for modulus, and 440 MPa for strength) with a good ductility (7.4%).

Automated summary

In this study, AlSi10Mg composites modified with SiC nanoparticles were successfully produced using a combination of methods. The influence of laser-energy-input (E-V) on the microstructure evolution and mechanical properties was systematically investigated. Results showed that SiC nanoparticles could refine the matrix grains, enhance strength and elongation, but might have a detrimental impact on tensile properties.