A thermo-mechanical modeling reduction approach for calculating shape distortion in SLM manufacturing for aero engine components

The Selective Laser Melting (SLM) of metallic powders, especially of high-strength nickel based alloys, allows for the manufacturing of aerospace 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 analyze different modeling approaches of the thermo-mechanical effects during 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 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 modeling effort and high computation duration and yet provide reliable deformation results.