Study of Geometric Imperfection of Lattice Structures Fabricated by Selective Laser Melting

Abstract

In this paper, the geometrical imperfections of lattice structures fabricated by selective laser metal melting machine were investigated. Due to the rapid development of additive manufacturing technology, the complex and precise cellular structures can be manufactured easier than before. However, in the manufactured specimen, there exists unavoidable geometrical imperfections, and they are affected by the laser conditions and the scale of objects. In our study, the lattices with various strand angle and diameter were fabricated by changing the laser conditions, and the actual imperfections were measured by X-ray CT and SEM machines. When the laser power increases, the excessive ovalization can be observed, which is due to the excessive melt flows along the major axis. Also, an excessive deviation of the diameter can be observed underside of each strand.