A computational reduction model for appraising structural effects in selective laser melting manufacturing

Selective Laser Melting (SLM) of metallic powders, especially of high-strength nickel based alloys, allows for the manufacturing of components of high shape complexity and load capacity. However, due to high temperature gradients, induced during laser processing, the structural properties and geometrical accuracy of components can be affected. This paper aims to analyse different modelling approaches of the thermo-mechanical effects in SLM manufacturing of aero-engine components, in order to determine in advance possible shape distortions. Hereby, a methodical model reduction is proposed and evaluated to allow the finite element analysis of larger components with reasonable computational time. Major process characteristics such as heat input, molten region geometry (i.e. macrographs), material deposition (i.e. layer thickness), temperature dependent material and powder properties, phase transformation, process sequences and convection effects are taken into consideration. The proposed model reduction aims to decrease time consuming modelling effort and high computation duration and yet provide reliable structural results.