Microstructure and mechanical properties of nano-WC reinforced AlSi10Mg fabricated by selective laser melting

Abstract

In order to further enhance the performance of the AlSi10Mg parts fabricated by selective laser melting, the WC/AlSi10Mg composite with 0.1%WC(mass fraction) was obtained by mixing the nano-WC and AlSi10Mg in mixing machine, and the specimen block was fabricated by the selective laser melting machine. By comparing the AlSi10Mg specimens fabricated by the same process, the effects of nano-WC on the microstructure formation and evolution of the microstructure and the mechanical properties of the microstructure were investigated. The results show that the WC/AlSi10Mg powder has good sphericity and the particle size distribution is concentrated in 20-60 μm. The WC/AlSi10Mg sample has the density of over 99% and hardness of about 158.89HV, which is 14.58% higher than that of the AlSi10Mg sample. The WC/AlSi10Mg samples grow uniformly and densely, with obvious molten pool lines. The inside of the crystal grain is α-Al matrix, and the boundary is a eutectic Si phase interposed with WC. The yield strength of the WC/AlSi10Mg sample reaches 337.75 MPa, the ultimate strength is as high as 514.00 MPa, and the elongation is 3.78%. Compared with the same process, AlSi10Mg samples are increased by 4.73%, 6.25% and 35.97%, respectively. Therefore, SLM-processed WC/AlSi10Mg composite parts have better application prospects than AlSi10Mg parts.

Keywords

• alsi10mg
• selective laser melting
• nano-wc
• microstructure
• mechanical property