Wang Guo-Lin, Zhou Hua-Jian, Zhou Hai-Chao, Liang Chen
School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang 212013, China.
Materials (Basel). 2023 Apr 22;16(9):3301. doi: 10.3390/ma16093301.
The co-extrusion process is widely used to produce composite tire treads with better performance. This study investigated the rubber co-extrusion flow process and quality influencing factors of tri-composite tire tread through numerical simulation and experimental methods. Here, RPA 2000 rubber processing analyzer was used to carry out rheological tests on the three rubber materials, the PTT viscoelastic constitutive model was fitted, and the fitting curves were in good agreement with the test data. Then, a three-dimensional viscoelastic numerical simulation model of the tri-composite tread co-extrusion process was established using Ansys Polyflow software. The parameter evolution technique is adopted in the model establishment to improve the calculation convergence. In addition, a global remeshing function is used to avoid excessive mesh deformation. A co-extrusion experiment is conducted to verify the model's accuracy using a tri-screw extruder. The extruded tread size error rate between the experiment and simulation is less than 6%. The variation of the velocity field, pressure field and shear rate field during extrusion is analyzed, and the formation mechanism of die swell is explained simultaneously. Finally, the influence of process parameters (inflow rate and traction speed) and die structure (convergence angle and thickness) on the extruded tire tread shape and quality was investigated, which can provide theoretical guidance for improving tread quality and production efficiency. Furthermore, the numerical simulation method can assist the design of the die plate in enhancing the efficiency of the die plate design.
共挤出工艺被广泛用于生产性能更优的复合轮胎胎面。本研究通过数值模拟和实验方法，对三元复合轮胎胎面的橡胶共挤出流动过程及质量影响因素进行了研究。在此，使用RPA 2000橡胶加工分析仪对三种橡胶材料进行流变测试，拟合了PTT粘弹性本构模型，拟合曲线与测试数据吻合良好。然后，利用Ansys Polyflow软件建立了三元复合胎面共挤出过程的三维粘弹性数值模拟模型。在模型建立过程中采用参数演化技术来提高计算收敛性。此外，使用全局重新划分网格功能来避免网格过度变形。利用三螺杆挤出机进行共挤出实验以验证模型的准确性。实验与模拟得到的挤出胎面尺寸误差率小于6%。分析了挤出过程中速度场、压力场和剪切速率场的变化情况，同时解释了离模膨胀的形成机理。最后，研究了工艺参数（流入速率和牵引速度）和模具结构（收敛角和厚度）对挤出轮胎胎面形状和质量的影响，可为提高胎面质量和生产效率提供理论指导。此外，数值模拟方法可辅助模板设计，提高模板设计效率。
