Abstract The layer flatness and interfacial strength for the direct ink writing (DIW)-fabricated multilayer sensors are two significant factors in dominating the printing precision and the structural integrity of the sensors, respectively. However, it is still a challenge to control the interfacial strength and layer flatness of the multilayer sensors due to the multiplicity of materials and inherent lines-to-plane forming process of DIW technology. Here we probe a set of DIW fabrication parameters to optimize the layer flatness and design the interfacial strength of the multilayer sensors. The nonlinear thickness-dependent interfacial strength is then measured by single-lap joints experiments, which can be further predicted by an analytical model and finite element simulations. Finally, the high precision and stability of the printed strain sensors with considerably flat layers and high interfacial strength are further tested under static and cyclic tensile loadings. This study provides a feasible approach for parametrically designing and precisely manufacturing multilayer sensors based on the widely used DIW technology.

中文翻译：

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通过直接墨水写入的多层复合结构的高精度电阻应变传感器：优化的层平整度和界面强度

摘要 直接墨水写入 (DIW) 制造的多层传感器的层平整度和界面强度分别是决定传感器打印精度和结构完整性的两个重要因素。然而，由于材料的多样性和DIW技术固有的线对平面形成过程，控制多层传感器的界面强度和层平面度仍然是一个挑战。在这里，我们探讨了一组 DIW 制造参数，以优化层平整度并设计多层传感器的界面强度。然后通过单搭接接头实验测量非线性厚度相关的界面强度，这可以通过分析模型和有限元模拟进一步预测。最后，在静态和循环拉伸载荷下进一步测试了具有相当平坦层和高界面强度的印刷应变传感器的高精度和稳定性。本研究为基于广泛使用的 DIW 技术参数化设计和精确制造多层传感器提供了一种可行的方法。