砂模3D打印是一种快速发展的砂模智能制造技术，能够对任意复杂形体进行几何造型。在实际应用中，砂模造型设计仍沿用传统设计思想，尚未充分发挥3D打印所带来的技术优势。由于传统砂模几何形体中存在冗余结构，直接影响打印效率，因此有必要结合3D打印技术优势对砂模结构进行设计优化，以提高生产效率、节约生产成本。在新工艺环境下，本文建立了一种砂模结构优化设计方法及其设计流程；以砂模壁厚作为优化参数，依据力学性能要求，建立了砂模结构优化设计模型；最终基于某厂铸造试验件进行了范例设计与仿真校核。优化设计后的试验件砂模在满足力学性能要求的前提下，体积优化率达到42.6%，有效提升3D打印砂模的生产效率与经济性。
As a novel rapid prototyping sand casting method, 3D-printing is capable of producing any complex mould, which makes further structure optimization of the sand mould possible. Because of the connection between the production speed of 3D-printing and the structure of mould, it is necessary to optimize structure of 3D printed sand mould. In this situation, an optimum design method of the 3D printed sand mould is established, and the design process is introduced. Based on the mechanical property requirements, the thickness of the sand mould is taken as the optimization parameter, and the optimum design model is established. In the end, the optimum design of the casting sample is completed. Results show that the volume of the sand mould is reduced by 42.6% after optimum structure design, thus the efficiency of production is raised, and the cost of the resin-bonded sand is reduced.
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