Multi-material topology optimization has become a promising method in structural design due to its excellent structural performance. However, existing research assumes that the multi-material structures are joined by welding, adhesive, or other methods that do not support reassembly and disassembly and are unsuitable for manufacturing, limiting the practical application of topology optimization. An interlocking joint is a type of connection between two parts where the shapes of the parts are designed to fit together precisely, the multi-material structure joined by interlocking joints can be easily reassembled repeatedly. To solve the joint problem of multi-material structure, this study proposes an assemblable interlocking joint generation method for multi-material topology optimization, the connection between material components is achieved through compression at the joint areas. To generate the interlocking joints, a novel interfacial partial stress constraint is proposed by converting a part of the interface bearing tensile stress into the interface bearing compressive stress. A novel filtering process is used to control the shape of the interlocking joints and the filtered tensile stresses are integrated by a P-norm function. To constrain the distribution area of material components and ensure structural manufacturability, dimensional constraints are applied. The sensitivity is based on the topological derivative and adjoint variable method. The proposed method was applied to several numerical examples including one manufactured prototype to demonstrate its effectiveness and contribution to the practical application of topology optimization.

中文翻译：

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一种基于界面部分应力约束和尺寸约束的多材料拓扑优化的可组装互锁接头生成方法


多材料拓扑优化由于其优异的结构性能已成为结构设计中一种很有前途的方法。然而，现有的研究假设多材料结构是通过焊接、粘合剂或其他不支持重新组装和拆卸且不适合制造的方法连接的，从而限制了拓扑优化的实际应用。互锁接头是两个零件之间的一种连接类型，其中零件的形状被设计为精确配合在一起，由互锁接头连接的多材料结构可以很容易地重复重新组装。为解决多材料结构的接缝问题，本研究提出了一种用于多材料拓扑优化的可组装联锁接缝生成方法，通过在接缝区域进行压缩来实现材料组件之间的连接。为了产生互锁节点，通过将界面的一部分承受拉应力转换为承受压应力的界面，提出了一种新的界面部分应力约束。使用一种新颖的过滤过程来控制互锁接头的形状，并通过 P-norm 函数对过滤后的拉伸应力进行积分。为了约束材料组件的分布区域并确保结构的可制造性，应用了尺寸约束。灵敏度基于拓扑导数和伴随变量方法。所提出的方法被应用于几个数值实例，包括一个制造的原型，以证明其有效性和对拓扑优化实际应用的贡献。