钛合金铆钉变形时易不均匀、易开裂，在碳纤维增强树脂基复合材料（CFRP）铆接过程中引入脉冲电流作用，软化铆钉并改善其塑性。研究了连接域内的热响应机制与温度场分布，基于能量守恒、焦耳热定律、热传导定律构建了静态焦耳热模型表征稳态换热铆接工况下的CFRP温度，考虑铆接过程电流波动、温度分布不均和热区域分散性建立了动态温度场模型预测铆接过程温升。结果表明：CFRP孔周一定辐射半径范围处温度与钉中心温度线性相关，模型准确模拟出了40 s内的过程温度。静态模型在11%误差以内精准预测了中心饱和温度，动态模型模拟的温升趋势与实测温度值吻合较好。热量传递的滞后性使得动态模型对快速温升时的温度预测存在误差，该误差随电流密度变大而增加，最大达17.15%。接头损伤评估表明过程温度控制在150℃内时可获得质量合格的铆接接头。
Titanium alloy rivets tend to become uneven and crack easily when deformed. Pulse current is therefore introduced in the riveting process of the Carbon Fibre-Reinforced Polymer (CFRP) to soften the rivets and improve their plasticity. The thermal response mechanism and temperature field distribution in the connection domain are studied. A static Joule heating model is constructed based on the conservation of energy, Joule's heat law, and the law of heat conduction to characterize the CFRP temperature under steady-state heat exchange riveting conditions. Considering the current fluctuation and the uneven temperature distribution during riveting and the dispersion of the hot zone, we establish a dynamic temperature field model to predict the temperature rise during the riveting process. The results show that the temperature within a certain radiation radius around the CFRP hole is linearly related to that of the nail center, and the model accurately simulates the process temperature within 40 s. The static model accurately predicted the central saturation temperature within an error of 11%, and the trend of temperature rise simulated by the dynamic model was in good agreement with the measured temperature value. The hysteresis of heat transfer leads to an error of the dynamic model in temperature prediction during rapid temperature rise. The error increases with the rising of the current density, and the maximum value reaches 17.15%. The joint damage assessment reveals that qualified riveted joints can be obtained when the process temperature is controlled within 150℃.
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