Due to its high printing resolution and fast printing speed, digital light processing (DLP) has become one of the most widely used additive manufacturing technologies. In a typical DLP printing, resin is photocured from liquid into solid accompanied by a large volume shrinkage, which often leads to shape distortion of printed structures. In this study, we investigated the volume shrinkage-induced distortion of DLP-printed parts by conducting experiments, theoretical modeling, and finite element analysis (FEA) simulations. Material property evolution coupled with volume shrinkage during photocuring was first modeled constitutively. The constitutive theory was then implemented into FEA simulations of the layer-by-layer DLP printing process to study the development of shape distortion due to volume shrinkage during printing. Experiments validated the efficiency of the proposed FEA simulations. FEA was further applied to help predict the shape distortion in printed microfluidic channels and overhanging structures where printing parameters for compensating for distortion can be designed based on FEA.

由于其高打印分辨率和快速打印速度，数字光处理 (DLP) 已成为应用最广泛的增材制造技术之一。在典型的 DLP 打印中，树脂从液体光固化为固体，伴随着较大的体积收缩，这往往会导致打印结构的形状变形。在本研究中，我们通过实验、理论建模和有限元分析 (FEA) 模拟研究了 DLP 打印部件的体积收缩引起的变形。材料特性演变与光固化过程中的体积收缩首先被本构建模。然后将本构理论应用于逐层 DLP 印刷过程的 FEA 模拟，以研究由于印刷过程中体积收缩导致的形状变形的发展。实验验证了所提议的 FEA 模拟的效率。进一步应用 FEA 来帮助预测印刷微流体通道和悬垂结构中的形状失真，其中可以基于 FEA 设计补偿失真的印刷参数。