In this work, two simple models to calculate the strain rate at which material deforms during the friction stir welding (FSW) process are proposed. In both cases, predictions are associated with operational parameters such as rotational and travel speed and tool pin radius. A first model is based on the analysis of the strain experienced by the material on the periphery of the pin associated with the rotation and displacement present during the joining process. The second one is based on the resemblance of FSW with an asymmetric rolling process in which a dramatic strain gradient takes place. Using these models, and employing fitting parameters, it is possible to estimate the mean deformation rate during the FSW process. Very reasonable values, which fall in the range of strain rate data reported in the literature, are obtained. This new view should allow determining equivalent experimental conditions (strain, strain rate, and temperature in conventional uniaxial tests) under which this joining process occurs. This is critical to predict weld quality.

在这项工作中，提出了两个简单的模型来计算在搅拌摩擦焊（FSW）过程中材料变形的应变率。在这两种情况下，预测都与诸如旋转和行进速度以及工具销半径之类的操作参数相关联。第一模型是基于对销的外围上的材料所经历的应变的分析，该应变与在接合过程中出现的旋转和位移相关。第二个是基于FSW与不对称轧制过程的相似之处，其中发生了急剧的应变梯度。使用这些模型并采用拟合参数，可以估计FSW过程中的平均变形率。获得了非常合理的值，该值落在文献中报道的应变率数据的范围内。这种新的观点应允许确定在这种条件下进行连接过程的等效实验条件（应变，应变率和常规单轴测试中的温度）。这对于预测焊接质量至关重要。