Effect of Si content on microstructure and thermo-physical properties of the joint of Si p /6063Al composite by laser melting deposition

摘要: Abstract Laser melting deposition (LMD), an additive manufacturing-based technology, was utilized to join Si p /6063Al composite creatively with different weight contents (Al-Si 5%, 12%, 20% and 30%). Influence of the content on constitutional phases, microstructural characteristics, thermo-physical properties layer by built-up weld beads investigated. Experimental results showed that increasing deposited could lead a marked increment both size volume precipitated phase, circled α-Al phase decreased as whole. The Si/Al interface began decrease for sample Al-Si30 wt.% due connection phases. within (Al, Si) eutectic were observed exhibit two sub-micron solidification morphologies, columnar grains equiaxed grains, respectively. In general, Si, thermal conductivity owing decreasing high conductivity, coefficient expansion (CTE) had same varying trend which attributed fraction stiff Si-Si contiguity.