Nonlinear Rheological Analysis of Yielding Behavior in Graphene Oxide Inks for Direct Ink Writing Printing
발표자
윤승원 (수원대학교)
연구책임자
심율희 (수원대학교)
공동저자
윤승원 (수원대학교), 심율희 (수원대학교)
초록
내용
Direct ink writing (DIW) requires precise control of ink rheology because the ink undergoes yielding during extrusion and structural recovery after deposition. However, the nonlinear rheological mechanisms governing these transitions remain unclear, limiting process optimization. In this study, graphene oxide (GO) ink was used as a model system to analyze yielding behavior using nonlinear rheology. GO was selected due to its high dispersibility and tunable microstructure. The loss modulus (G″) was decomposed into recoverable and unrecoverable components using a strain decomposition method based on recovery rheology. This approach enables quantitative comparison of brittle and ductile yielding behaviors. The results demonstrate that recovery rheology provides an effective framework for describing yielding transitions and offers practical guidelines for optimizing DIW processing.