Microstructure and Mechanical Properties of In-Situ TiB₂ Particle Reinforced AlSi10Mg Composite Coatings Produced by Cold Spraying

This study investigates the effect of heat treatment on the microstructure and tribological properties of TiB₂-reinforced AlSi₁₀Mg composite coatings produced by cold spraying. SEM and XRD analysis showed that the microstructure of the feedstock powder was well preserved in the as-sprayed material with uniformly distributed TiB₂ nanoparticles, some aggregated clusters, and a cellular-like network of fine eutectic Si particles embedded in an aluminum matrix. With increasing heat treatment temperature, the Si particles grew larger in size, but significantly fewer in number and a reduction in microhardness was observed due mainly to the elimination of the work hardening effect and coarsening of the Si particles.