A study on tensile properties of Alloy 709 at various temperatures
A study on tensile properties of Alloy 709 at various temperatures
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709合金不同温度拉伸性能研究
DOI：
10.1016/j.msea.2018.06.089
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
A. Rabiei
中科院分区：
文献类型：
--
作者：
S. Upadhayay;Hangyue Li;P. Bowen;A. Rabiei
近年来，在从化石燃料和替代的“清洁”来源（如核裂变）生产能源方面取得了一些进展。这些进步是由于需要更有效的系统，以优化使用正在枯竭的化石燃料储备，并将重点转移到更清洁的能源。任何发电循环的效率取决于结构材料承受增加的峰值操作温度的能力。先进的奥氏体不锈钢由于其强度、耐腐蚀性、可焊接性和奥氏体相稳定的温度范围广而成为下一代核电站的结构材料。709合金是一种新开发的先进奥氏体不锈钢，本文对其进行了研究。在这项研究中，在原位扫描电子显微镜（SEM）加载和加热阶段，配备了电子背散射衍射（EBSD），在不同的温度下，对狗骨状样品的合金709进行拉伸试验。原位实验表明，该材料主要适应在较低温度下的滑移变形。在较高温度下，晶界处的空隙形成和聚结先于滑移。尽管在所有高温下裂纹的萌生都是沿晶的，但裂纹在材料中的扩展和最终断裂都是穿晶韧性的。此外，在空气中在550、650和750 °C下对较大的圆柱形样品进行拉伸测试。在这些温度下，在空气中和现场进行的测试结果一致。
In recent years, there have been several advancements in energy production from both fossil fuels and the alternate “clean” sources such as nuclear fission. These advancements are fueled by the need for more efficient systems that will optimize the use of the depleting fossil fuel reserves and shift the focus to cleaner sources of energy. The efficiency of any power generation cycle is dependent on the ability of the structural material to withstand increased peak operating temperatures. Advanced austenitic stainless steels have been in the focus as structural material for the next generation nuclear power plants, due to their strength, corrosion resistance, weldability and the wide range of temperatures at which the austenite phase is stable. Alloy 709, a recently developed advanced austenitic stainless steel, is being investigated in this paper. In this study, tensile tests were conducted on dog-bone samples of Alloy 709 in an in-situ scanning electron microscope (SEM) loading and heating stage, equipped with electron backscatter diffraction (EBSD), at various temperatures. The in-situ experiments indicated that the material primarily accommodated deformation by slip at lower temperatures. Void formation and coalescence at grain boundaries preceded slip at higher temperatures. Although crack initiation at all elevated temperatures was intergranular, the crack propagation through the material and the final fracture was transgranular ductile. Additionally, tensile tests were conducted on larger cylindrical samples at 550, 650 and 750 °C in air. The results of tests conducted in air and in-situ were found to be in agreement, at these temperatures.