The thermal loading during the curing process of an adhesive-bonded joint induces residual stresses in the joint, thereby affecting its performance. The problem becomes worse in the case of a multi-material joint involving varying coefficients of thermal expansion (CTE) for different parts. A novel approach was developed to model the properties of automotive grade structural adhesives during the heat curing process. The material model was divided into two components: curing kinetics model and viscoelastic mechanical model. The models were calibrated using experimental data from Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA) tests performed on an epoxy-based single-component adhesive. The calibrated material model parameters were fed into a finite element simulation and the prediction results were compared to a unique set of experiments utilizing two substrate combinations of adhesive-bonded single lap shear joints. An excellent agreement between the simulated and experimental results (displacement across the bond, force applied by the adhesive) was achieved. The modeling results give a better understanding of the residual stresses and agree with the experimental trend on the effect of bondline thickness on the joint.

粘接接头的固化过程中的热负荷会在接头中产生残余应力，从而影响其性能。在涉及不同零件的热膨胀系数（CTE）变化的多材料接头的情况下，问题变得更加严重。开发了一种新颖的方法来模拟汽车级结构胶在热固化过程中的性能。材料模型分为两个部分：固化动力学模型和粘弹性力学模型。使用来自差示扫描量热法（DSC）和动态机械分析（DMA）测试的实验数据对基于环氧树脂的单组分胶粘剂进行校准。将校准后的材料模型参数输入到有限元模拟中，并将预测结果与使用粘合剂粘合的单搭接剪切接头的两种基材组合的一组独特实验进行比较。在模拟结果和实验结果（键之间的位移，粘合剂施加的力）之间达成了极好的一致性。建模结果可以更好地理解残余应力，并且与粘结层厚度对接缝影响的实验趋势相吻合。