In recent years, the growing trend of using polymer materials in various industries has led to significant improvements in the methods of production and bonding of polymer materials. The present study aimed to optimize the flexural strength of polypropylene sheets welded by the friction-stir method, which is considered as one of the most efficient methods in this field. The surface quality and mechanical properties of the components produced in this method highly rely on the parameters of rotational speed, linear speed, geometry, and tool tilt. Therefore, this research seeks to evaluate the effect of these parameters on three different levels, both experimentally and statistically, in order to investigate the welding flexural strength. By applying the analysis of variance and Box–Behnken response surface methodology, the results revealed the existence of a significant relationship between the properties and parameters of the process and the possibility to examine the effect of the interaction of different parameters in the process using mathematical modeling and Chart analysis. In addition, optimal models were introduced through process optimization so that the flexural strength of the weld joint was increased by up to 96% of that of the base specimen, after conducting further experimental tests, resulting in confirming the optimal model. Finally, the efficiency of the designed model was evaluated by comparing the measurement errors obtained from the experimental results and the prediction of the model.

中文翻译：

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摩擦搅拌焊接法粘合焊接聚丙烯板的抗弯强度估算和优化

近年来，高分子材料在各行各业中使用的日益增长的趋势导致高分子材料的生产和粘合方法的显着改进。本研究旨在优化通过摩擦搅拌法焊接的聚丙烯片材的弯曲强度，该方法被认为是该领域最有效的方法之一。用这种方法生产的零件的表面质量和机械性能高度依赖于转速、线速度、几何形状和工具倾斜度等参数。因此，本研究旨在通过实验和统计来评估这些参数在三个不同水平上的影响，以研究焊接弯曲强度。通过应用方差分析和 Box-Behnken 响应面方法，结果表明，过程的特性和参数之间存在显着关系，并且可以使用数学建模和图表分析来检查过程中不同参数相互作用的影响。此外，通过工艺优化引入优化模型，使焊接接头的抗弯强度比基体试样的抗弯强度提高高达96%，经过进一步的实验测试，最终确定了优化模型。最后，通过比较实验结果得到的测量误差和模型的预测结果来评估设计模型的效率。