Effects of laser interface sintering on monolayer copper micro-particles using a carbon dioxide pulsed laser system

Abstract

Manufacturing of complex and intricate structures using the laser sintering process are in great demand for various applications such as thermal management, light weight structures, filtration, biomedical systems, and electronic components. Different methods of laser sintering can offer a variety of functions for the structures. However, due to the numerous amounts of factors affecting the quality of sintering, and the bonding between the particles, studies are carried to analyze these factors and their effects on the fabricated structures. The single-component laser surface-sintering method has the unique ability of generating porosity throughout the structure. This study shows the design and methodology of installing a CO2 pulsed microsecond laser capable of these functions, as well as the procedure and analysis of factors affecting successful sintering of copper micro-particles. Results show the successful fabrication of laser sintering of a monolayer of copper micro-particles using a pulse period of 1000 ?s, pulse width of 150 ?s and a defocused beam with a spot size of 4.73 mm. Experimental tests such as, surface roughness, porosity and thermal conductivity tests and simulations were also carried out to validate the quality of sintering, as well as comparing the results with that of conventionally (furnace) sintered samples to show similar manufacturing quality. The obtained results provide a better understanding and a foundation for the steps towards the fabrication of a 3D porous structure.