Microstructural evolution and mechanical performance of in-situ TiB2/AlSi10Mg composite manufactured by selective laser melting

In-situ TiB2/AlSi10Mg composites were prepared by casting, gas atomization, and selective laser melting (SLM), respectively. Microstructural evolution of the in as-cast, atomized, SLMed investigated. Compared with as-cast composite, sample has no texture is composed extremely fine grains crystal cells. The in-situ TiB2 particles uniformly distribute over grain boundaries, acicular Si phase replaced a network there are nano-sized precipitations cell. formation this microstructure due to continuous solidification non-equilibrium eutectic Al–Si during rapid cooling process SLM. composite obtains excellent strength (tensile ? 451 MPa, bending 674 MPa), hardness (?151 HV0.1) good friction coefficient (?0.4), which higher than that AlSi10Mg alloy. mechanism particular structure its strengthening effect discussed.