Feng Tian-Hao, Xie Xing-Fei, Liu Yang, Qu Jing-Long, Lyu Shao-Min, Du Jin-Hui, Ruan Jing-Jing, Zhu Li-Long
Institute for Advanced Studies in Precision Materials, Yantai University, Yantai 264005, China.
Beijing GAONA Materials and Technology Co., Ltd., Beijing 100081, China.
Materials (Basel). 2025 Mar 14;18(6):1288. doi: 10.3390/ma18061288.
This study systematically investigated the microstructural evolution and mechanical properties of GH4780 superalloy under various solution treatment conditions. Experimental results reveal a strong temperature dependence of grain growth kinetics, with the average grain diameter increasing from approximately 20 μm to 194 μm as the solution temperature rises from 1020 °C to 1110 °C. Mechanical testing demonstrates that grain coarsening reduces the yield strength by 19% at room temperature (from 920 MPa to 743 MPa) and by 9.5% at 760 °C (from 707 MPa to 640 MPa), primarily due to decreased grain boundary density and enhanced dislocation mobility. High-temperature deformation mechanisms were characterized, showing that the reduced grain boundary area facilitates dislocation motion while compromising strength. Furthermore, a grain growth kinetic model was developed, providing a quantitative prediction of microstructural evolution. These findings offer significant guidance for improving the high-temperature performance of GH4780 superalloy by optimizing heat treatment processes.
本研究系统地研究了GH4780高温合金在各种固溶处理条件下的微观结构演变和力学性能。实验结果表明，晶粒生长动力学对温度有很强的依赖性，随着固溶温度从1020℃升至1110℃，平均晶粒直径从约20μm增加到194μm。力学测试表明，晶粒粗化使室温下的屈服强度降低了19%（从920MPa降至743MPa），在760℃时降低了9.5%（从707MPa降至640MPa），这主要是由于晶界密度降低和位错迁移率提高所致。对高温变形机制进行了表征，结果表明，晶界面积的减小有利于位错运动，但会降低强度。此外，还建立了晶粒生长动力学模型，对微观结构演变进行了定量预测。这些发现为通过优化热处理工艺提高GH4780高温合金的高温性能提供了重要指导。
