A Critical Review of the Effects of Selective Laser Melting Process on AlSi10Mg Alloy
Comfort Akwonya Adadu1, Emmanuel Ocheola Oko2, Mike Airelo Enaboifo3
1Department of Vocational and Technical Education, Benue State University, Makurdi
2Department of Mechanical Engineering, Benue State Polytechnic, Ugbokolo-Nigeria,
3Department of Agricultural Engineering, University of Benin, Benin City, Nigeria
Email: 1comfortadadu@yahoo.com, 3michael.enaboifo@uniben.edu
ABSTRACT
Automobile and Aerospace industries are the key players in the application of Aluminium and its alloys due to their suitable properties. AlSi10Mg is a suitable cast alloy with good mechanical properties. Meanwhile, processing AlSi10Mg powder by selective laser melting poses some difficulty due their high reflective and conductive properties coupled with the surface oxide films present in the powders. Selective laser melting process of the alloys particularly AlSi10Mg was reviewed to understand the effects of laser processing and powder properties on the microstructure and mechanical properties of the manufactured part. The hydrogen porosity in the alloy can be reduced, achieving a pore density of 90% by internal drying by laser. The hydrogen pores present in the powder due to moisture on the surface and the oxygen contained in the substrate can be reduced by drying the powder. External powder drying by 200oC reduced hydrogen pores by approximately 50%. Porosity absence in the alloy using single tracks and layers were achieved. The Fine microstructure observed in the core of the melt pools was due to rapid cooling. Parts manufactured by selective layer melting surpass that of casting in mechanical properties.
Keywords: selective laser melting; aluminium alloys; microstructure; porosity; mechanical properties
