Complex estimation of mechanical properties of SLM-printed gyroid AlSi10Mg structures – experimental and FE analysis

Gyroid triply periodic minimal surfaces (TPMS) structures are vastly considered for thermal applications as they provide better surface to volume ratio and ensure mechanical properties. Its properties are significantly influenced by cell size, printing process, printing direction and volume fraction. To ensure the mechanical strength of the design, accurate stress measurements need to be done. TPMS structures do not behave the same as conventional structures or lattice structures due to their continuous curvature and nonlinearity. To evaluate accurate properties of TPMS structures, complex finite element approaches are needed. This study introduces complex finite element methods to evaluate accurate properties of the TPMS structures. Gyroid structures were also 3d-printed and tested to validate the simulation results. These structures were printed with varying printing direction and varying volume fractions using the selective laser melting (SLM) process. Surface roughness of the samples was recorded before and after post-processing. Tensile and compression tests were performed to investigate the impact of varying volume fraction and printing direction on mechanical behavior. Important finding of this paper is the precise and experimentally validated finite element method that could evaluate accurate mechanical properties of TPMS structures. Based on experimental data, predictive equations are designed which could predict the properties of the gyroid structure for any volume fraction.