基于细观位错机理的单晶合金高温力学性能模拟

利用基于细观位错运动的蠕变筏化模型对镍基单晶合金CMSX-4在1223K下的拉伸、蠕变、循环、蠕变疲劳交互及各向异性进行模拟,结果表明:拉伸过程中应变率较高时应力略微下降的现象;蠕变条件下应力越大则蠕变第1阶段越明显,而蠕变稳定阶段越短的趋势;蠕变疲劳交互作用下的应力松弛和应变增大;以及单晶3个典型晶体取向的循环应变硬化特征。通过与试验结果对比,验证了此模型在较高温度下对单晶合金性能的综合模拟能力。

Simulation of Single Crystal Superalloy Mechanical Properties Based on Microstructure Dislocation Mechanism

The tension, creep, cycle, creep-fatigue interaction and anisotropic performance of Ni base single crystal superalloy CMSX--4 at 1223K were simulated by thecreep rafting model based on the microstructure dislocation. The result shows that the stress declines slinghtly at higher strain rate during tension. The greater the stress, the more obvious the first stage of creep and the shorter the creep stable stage under the creep. The stress is relaxed and the strain increases under creep-fatigue interaction, and the cyclic strain tends to be harden at three typical crystal orientation of Ni base single crystal. Comparing with the test results, The simulation verify that the model has comprehensive simulation capability for the performance of Ni base single crystal at higher temperature.