The moving morphable component (MMC) topology optimization method, as a typical explicit topology optimization method, has been widely concerned. In the MMC topology optimization framework, the surrogate material model is mainly used for finite element analysis at present, and the effectiveness of the surrogate material model has been fully confirmed. However, there are some accuracy problems when dealing with boundary elements using the surrogate material model, which will affect the topology optimization results. In this study, a boundary element reconstruction (BER) model is proposed based on the surrogate material model under the MMC topology optimization framework to improve the accuracy of topology optimization. The proposed BER model can reconstruct the boundary elements by refining the local meshes and obtaining new nodes in boundary elements. Then the density of boundary elements is recalculated using the new node information, which is more accurate than the original model. Based on the new density of boundary elements, the material properties and volume information of the boundary elements are updated. Compared with other finite element analysis methods, the BER model is simple and feasible and can improve computational accuracy. Finally, the effectiveness and superiority of the proposed method are verified by comparing it with the optimization results of the original surrogate material model through several numerical examples.

In two-scale topology optimization, enhancing the connectivity between adjacent microstructures is crucial for achieving the collaborative optimization of micro-scale performance and macro-scale manufacturability. This paper proposes a two-scale concurrent topology optimization strategy aimed at improving the interface connection strength. This method employs a parametric approach to explicitly divide the micro-design domain into a “boundary connection region” and a “free design domain” at the initial stage of optimization. The boundary connection region is used to generate a connection layer that enhances the interface strength, while the free design domain is not constrained by this layer, thus fully exploiting the design potential of the material layout. During the optimization process, the solid isotropic material with penalization (SIMP) method is first used to optimize the material distribution in the free design domain, and filtering and projection techniques are employed to alleviate numerical instability and obtain a clear topological structure. Subsequently, the effective performance of the microstructure is calculated through homogenization and transferred to the macro-scale for global response analysis. Throughout the iterative process, the geometry of the connection layer remains unchanged, and only the free design domain is optimized, thereby achieving a balance between high performance and good manufacturability. The effectiveness of the proposed method is verified through numerical examples.