Laser-selective melting and forming technology for CNTs/Al composites

With the development and widespread application of high tech, complex industrial production increases the requirements for the performance and structure of metal materials. In order to improve the performance of metal materials and reduce industrial production costs, a laser selective melting forming method for carbon nanotubes (CNTs)/ aluminum (Al) composite materials was proposed. The composite material powder was prepared by wet mixing followed by ball milling method. CNTs and N-methylpyrrolidone (NMP) were mixed and dispersed using an ultrasonic cleaning machine for 40 minutes to reduce the compactness of CNTs clusters. Then, a finite element model for laser selective melting forming of CNTs/Al composite materials was constructed, and its application effect was tested and analyzed. The results showed that the density of aluminum based composite materials could reach up to 95%. The wear coefficient remained around 0.3, which was reduced by 0.35 compared to aluminum alloy materials. The highest strength and conductivity were 410 MPa and 68%, respectively, which were 240 MPa and 50% International Annealed Copper Standard (IACS) higher than that of aluminum alloy materials. The coefficient of thermal expansion remained at stable levels above 7×10-6 /K. Therefore, the addition of CNTs in laser selective melting forming of aluminum matrix composites had optimized the mechanical properties of aluminum matrix composites, improved conductivity, thermal stability, and wear resistance, and broadened the application range of aluminum matrix composites. © 2023 Journal of Biotech Research