AI 中文总结
该研究基于哈密顿原理建立热-力-相变耦合的多物理场模型，结合NEM方法，通过ANSYS三维模拟验证其可再现TTT行为并预测玻璃增材制造的残余应力与翘曲。
AI 中文摘要
玻璃增材制造本质上涉及包含极端加热和快速冷却速率的复杂热历史，这些极端条件直接决定了打印材料的最终微观结构和力学完整性。本研究提出了一种基于扩展哈密顿原理的多物理场材料模型，建立了有限应变下热、力学和相变过程耦合的统一变分框架。该公式整合了一阶熔化和二阶玻璃化转变的严格热力学描述，以及考虑热膨胀、相变特定密度变化和黏弹性变形的运动学分解。采用温度相关的黏度模型来捕捉玻璃化固有的微观结构动力学冻结特性。数值实现使用整体式邻域单元法（NEM）求解热传导方程，确保计算效率和稳定性。材料点层面的数值研究验证了该模型在不同冷却速率下再现时间-温度-转变（TTT）行为的能力。此外，在ANSYS中对激光沉积工艺进行的三维有限元模拟，展示了由相变动力学与黏滞弛豫相互作用导致的残余应力累积和宏观翘曲。
英文摘要
Additive manufacturing of glass inherently involves complex thermal histories characterized by extreme heating and rapid cooling rates. These extreme conditions directly govern the final microstructure and mechanical integrity of the printed material. This work presents a comprehensive multi-physics material model derived from the extended Hamilton principle, establishing a unified variational framework for coupled thermal, mechanical, and phase transformation processes at finite strains. The formulation integrates a rigorous thermodynamic description of first-order melting and second-order glass transitions with a kinematic split accounting for thermal expansion, phase specific density changes, and viscoelastic deformation. A temperature dependent viscosity model is employed to capture the kinetic freezing of the microstructure inherent to vitrification. The numerical implementation utilizes a monolithic Neighbored Element Method (NEM) for the solution of the heat equation, ensuring computational efficiency and stability. Numerical investigations at the material point level validate the models ability to reproduce Time-Temperature-Transformation (TTT) behavior under varying cooling rates. Furthermore, three dimensional Finite Element simulations in ANSYS of a laser-based deposition process demonstrate the accumulation of residual stresses and macroscopic warpage resulting from the interplay between phase transformation kinetics and viscous relaxation.
