A study of the microstructure and the mechanical properties of an Al Si Ni alloy produced via selective laser melting

Al-Si-Ni samples were produced via selective laser melting (SLM) by mixing AlSi10Mg and pure nickel powders. The mixing rate was chosen in order to obtain a chemical composition close to the eutectic and with the aim of exploiting a very narrow solidification temperature range. The building parameters were optimised to reduce the porosity values. Samples produced with the optimised process parameters were then characterized in terms of microstructures and hardness. The results show that even if some Al3Ni agglomerates were found, the SLM allows a good dispersion of the nickel within the alloy. The hardness tests revealed that the introduction of nickel strongly increased the hardness of the alloy. This was also demonstrated using nanoindentation measurements.