TopFat methodology implemented in a commercial software: benchmarking validation

Abstract

In recent years, Additive Manufacturing (AM) techniques for metal alloys, such as Selective Laser Melting (SLM) and Electron Beam Melting (EBM), experienced significant improvements in terms of process speed, cost reduction and overall repeatability. For this reason, the use of AM components has significantly increased. Moreover, the combined use of Topology Optimization (TO) algorithms and AM production processes has permitted to manufacture components with optimized stiffness mass distribution. When components are designed with TO algorithms, constraints on the maximum allowable stress within the component, e.g. the yield stress or the fatigue limit if quasi-static or cyclic loads are applied, respectively, are set to guarantee their structural integrity under several loading conditions. However, even with optimized process parameters, detrimental manufacturing defects, like pores, cluster of pores and lack of fusion defects, can form within the component affecting the fatigue response and lowering the fatigue limit. Therefore, it is crucial to consider the influence of defects when AM components are designed. To this aim, the Authors recently developed a property TO code, named TopFat, that provides the optimized topology by also considering the influence of defects on the fatigue response. In the present paper, the developed TopFat methodology is implemented by using a commercial software. The optimized topologies for literature traditional benchmarks obtained with the property code are compared with those obtained with the TopFat methodology implemented by using a commercial software. The differences between the two topologies are highlighted and discussed, with the aim of showing that the TopFat methodology can be reliably used for the design against fatigue failures from defects even with TO algorithms available in commercial software.