An Improved Density-Based Design Method of Additive Manufacturing Fabricated Inhomogeneous Cellular-Solid Structures

Abstract

Benefited from the rapid development of additive manufacturing (AM), inhomogeneous cellular structures have attracted many interests for their superior structural and functional performance. Recently proposed density-based design methods have been shown to provide great computational efficiency and obtain structures with excellent performance. To achieve better structural performance while considering AM constraints, an improved density-based design method which introduces solid and void units into the design domain is proposed in this paper. First, based on homogenization theory and solid-body analysis, unit parameters of different preset unit relative densities are determined. And a unit effective property interpolation model is constructed. Then, the macro relative density layout is optimized with density methods. In the optimization process, an efficient density filter is proposed to increase the optimization domain and satisfy minimal feature size constraint. Finally, the structure reconstruction algorithm automatically constructs the optimized cellular structure based on the unit and density information obtained in the first two processes. Numerical examples show that the proposed method efficiently obtains inhomogeneous cellular structures with better performance, compared with existing density-based methods.