【摘要】 研究了180℃下不同加载应力水平对2195铝锂合金的蠕变时效行为，并建立了相应的统一蠕变时效本构模型。结果表明：无论载荷应力如何，蠕变曲线均呈现两阶段特性，且总蠕变应变随着载荷应力的增加而增大；应力越大，相同时效时间下合金的抗拉强度和屈服强度越高，断后伸长率越低。250 MPa下时效合金的屈服强度和抗拉强度比200 MPa时效合金的分别高约17.4%和15.5%,断后伸长率低约27.8%。将试验值与预测值进行对比，发现建立的本构模型能够很好地预测不同加载应力下的蠕变变形和屈服强度，最大相对误差分别为9.5%和8.4%,证明了模型的可靠性。更多还原

【Abstract】 Creep aging behavior of 2195 Al-Li alloy under different applied stresses at 180 ℃ was investigated, and a corresponding unified creep aging constitutive model was established. The results indicate that regardless of the applied stress, the creep curves exhibit a two-stage characteristic, and the total creep strain increases with the increase of applied stress. A higher stress leads to higher tensile strength and yield strength, but lower elongation after fracture of the alloy under the same aging time. Compared with the alloy aged at 200 MPa, the yield strength and tensile strength of the alloy aged at 250 MPa are approximately 17.4% and 15.5% higher, respectively, while the elongation after fracture is approximately 27.8% lower. By comparing the measured values with the calculated values, it is found that the established constitutive model can well predict the creep deformation and yield strength under different applied stresses, with the maximum relative errors of 9.5% and 8.4%, respectively, which proves the reliability of the model.更多还原