Printability Enhancement and Tensile Property Improvement Via Developing in Situ Synthesized Carbon Nanotubes-Al Composite Powder

Abstract

A strategy of powder surface functional modification involving in situ synthesizing carbon nanotubes (CNTs) on Al powder is described to address the poor forming ability and inferior mechanical properties of 3D printed Al parts. Coating CNTs on Al powder significantly reduced the laser reflectivity and enhanced the printability. CNTs contributed to reinforcement after printing and enhanced the tensile properties. The printing behavior of powder, the distribution of reinforcement, and tensile properties of printed samples were optimized by tuning the CNT-content. From the viewpoint of forming quality and strengthening capability of reinforcement, the CNT-content was optimized at 0.96 wt.%. An increase of 61% in the yield strength was achieved in the printed sample with ductility similar to the printed monolithic Al sample.

Keywords: A. Metal-matrix composites (MMCs), B. Mechanical properties, E. Powder processing, E. Surface treatments