Ply-ply slippage is one of the key deformation mechanisms occurring during hot press-forming of thermoplastic composite laminates. Advanced forming simulations, required for defect-free manufacturing, rely on accurate constitutive models for these deformation mechanisms. In this work, we propose a relative simple, yet accurate, transient model to describe the start-up friction response of UD C/PAEK tapes. The model combines a White–Metzner viscoelastic fluid with a state-rate model for the evolution of wall slip near the fiber–matrix interface, describing the disentanglement of surface polymer chains followed by the settlement of these chains in a new equilibrium state. This allows prediction of the stress growth at start-up and the transition from peak to steady-state friction, from smooth to sharp with increasing sliding rate, as well as the magnitude of the peak and steady-state friction. We obtained a good correlation between the modeled and measured friction response for different sliding rates.

层间滑移是热塑性复合材料层压板热压成型过程中发生的关键变形机制之一。无缺陷制造所需的先进成形模拟依赖于这些变形机制的精确本构模型。在这项工作中，我们提出了一个相对简单但准确的瞬态模型来描述 UD C/PAEK 胶带的启动摩擦响应。该模型将 White-Metzner 粘弹性流体与纤维-基体界面附近壁滑移演化的状态速率模型相结合，描述了表面聚合物链的解开，以及这些链在新平衡状态下的沉降。这样可以预测启动时的应力增长以及从峰值摩擦到稳态摩擦的转变，随着滑动速率的增加从平滑到急剧的转变，以及峰值和稳态摩擦的大小。我们在不同滑动速率下的建模摩擦响应和测量摩擦响应之间获得了良好的相关性。