AI 中文总结
该研究针对PolyJet打印的Agilus与Vero数字混合聚合物，建立统一本构模型，捕捉其组分依赖的非线性粘弹粘塑性行为，可预测未校准混合物响应，为多材料结构设计提供基础。
AI 中文摘要
多材料PolyJet打印技术可制备弹性体光聚合物（Agilus）与玻璃态光聚合物（Vero）的体素级数字混合物，形成室温响应范围从弹性体到玻璃态的材料家族，但对该家族的统一描述一直颇具挑战。在近三个数量级的应变率下开展的大变形单轴压缩实验，揭示了随组分连续变化的非线性、率相关加载-卸载响应，从可恢复的弹性体滞后行为到玻璃态屈服，伴随屈服后软化、硬化及显著残余应变。动态力学分析（DMA）表明，每种混合物均具有单一玻璃化转变温度（$T_g$），该温度随Vero组分占比和频率升高而向高温偏移，因此组分的作用与温度或加载率类似。这种时间-组分等效性促使研究者为整个材料家族构建统一本构结构，而非为每种混合物单独设置属性集：该结构包含平衡超弹性网络，以及三个非平衡、率相关分支，分别承载 reptational（链缠结）、分子间及玻璃态阻力，其属性以两个端点为锚点，通过平滑的组分标度律进行插值。该模型可捕捉全部7种已校准组分的压缩响应，并仅通过标度律预测未参与校准的混合物。将预测应力分解至各分支显示，随Vero含量和率升高，载荷从弹性体机制向玻璃态机制传递，功从弹性存储向耗散转变。DMA在小应变下映射的玻璃化转变因此控制着大应变变形机制。该框架为数字混合聚合物提供了紧凑、基于物理的描述，并为功能梯度、结构化多材料结构的设计提供了预测基础。
英文摘要
Multi-material PolyJet printing produces voxel-scale digital mixtures of an elastomeric photopolymer (Agilus) and a glassy photopolymer (Vero), giving a material family whose room-temperature response ranges from elastomeric to glassy; a unified description spanning the family has remained challenging. Large-deformation uniaxial compression over nearly three orders of magnitude in strain rate reveals a nonlinear, rate-dependent load-unload response that evolves continuously with composition, from recoverable elastomeric hysteresis to glassy yield with post-yield softening, hardening, and substantial residual strain. Dynamic mechanical analysis (DMA) shows that each mixture has a single glass transition temperature ($T_g$) that shifts to higher temperature with both Vero fraction and frequency, so composition acts much as temperature or loading rate does. This time-composition equivalence motivates one constitutive structure for the whole family rather than a separate property set per mixture: an equilibrium hyperelastic network with three non-equilibrium, rate-dependent branches carrying reptational, intermolecular, and glassy resistance. Its properties are anchored at the two endpoints and interpolated by smooth composition scaling laws. The model captures the compression response of all seven calibrated compositions and predicts a withheld mixture from the scaling laws alone. Resolving the predicted stress into its branches shows the load passing from the elastomeric to the glassy mechanism, and the work from elastic storage to dissipation, as Vero content and rate rise. The glass transition that DMA maps at small strain therefore governs the large-strain deformation mechanisms. The framework gives a compact, physically based description of digitally mixed polymers and a predictive basis for designing functionally graded, architected multi-material structures.
Comments16 figures; updated citation DOI
