Topology optimization of thermal conductive support structures for laser additive manufacturing

This paper presents a topology optimization approach to design support structures with efficient thermal conductive capabilities for powder-bed based laser additive manufacturing (AM). A transient heat transfer model is proposed to simulate the temperature distribution of the point-by-point and layer-upon-layer AM process. The process model is seamlessly integrated into a density based structural topology optimization method with an adjoint based sensitivity analysis and a gradient based optimization. For a given prototype shape, the layout of the corresponding support structure is designed such that the thermal energy during the fabrication process can be efficiently transferred from the laser path to a prescribed heat sink. Besides, an overhang constraint is proposed and used together with an AM filter to avoid overhang features in both the optimized support structure and the prototype, ensuring the overall manufacturability. Numerical examples and discussions are given to demonstrate its applicability. (C) 2019 Elsevier B.V. All rights reserved.