In the process of arc additive manufacturing

aluminum alloy is easy to cause inhomogeneous microstructure distribution and solute segregation due to continuous heat accumulation

leading to its anisotropic properties. In order to solve this problem

the tungsten inert gas (TIG) additive manufacturing process with addition of TiB2 nanoparticles was designed. In the process of wire and arc additive manufacturing

TiB2 nanoparticles were added to the deposition samples by surface pre-coating. The effects of different mass fraction of TiB2 nanoparticles on the microstructure of AlSi5 alloy were compared and studied. The results show that the microstructure inhomogeneity of AlSi5 aluminum alloy was obviously improved with the mass fraction of TiB2 increased. The grain size decreased from 226μm to 85.6μm with the addition of 1.5% TiB2

and the texture on (110) and (112) basal planes decreased obviously

besides the maximum orientation density was decreased. The hardness and elastic modulus of the deposited layer were significantly improved with addition of TiB2 nanoparticles. The value of hardness increased from 879MPa to 1253MPa

and the elastic modulus increased from 81.9GPa to 88.3GPa.