Effect of aging on failure mechanism of Alloy 709 at various temperatures
Effect of aging on failure mechanism of Alloy 709 at various temperatures
复制标题
不同温度下时效对709合金失效机制的影响
DOI：
10.1016/j.matchar.2020.110750
复制
发表时间：
2021
影响因子：
4.7
通讯作者：
Lall A
中科院分区：
文献类型：
--
作者：
Lall A
709合金是一种新型奥氏体不锈钢，具有高温蠕变强度、焊接性和耐腐蚀性。这些特性使该材料适用于下一代核电站的结构。在核电站的恶劣环境中长时间忍受高温会导致材料的热老化。因此，在709合金应用于下一代电站之前，研究热时效对709合金组织和力学性能的影响是非常必要的。在这项研究中，热加工（锻造+轧制），退火和淬火的709合金铸锭在650 °C下在空气中时效2000小时，然后在各种温度下进行测试高达850 °C的原位加热加载扫描电子显微镜（SEM）配备能量色散谱（EDS）和电子背散射衍射（EBSD）。研究了拉伸温度和时效对原始态和时效态试样拉伸过程中显微组织演变的影响。由于动态应变时效（DSA）的影响，接收态和时效态样品在高温下都显示出锯齿状和延展性下降。DSA活性的发生在500 °C-750 °C的温度范围内，在原样和550 °C - 650 °C的老化样品中。老化样品显示出较小的伸长率，伴随着断裂表面上较浅的凹痕，表明与原样样品相比，韧性失效机制较少。使用SEM断口分析的断裂表面上的失效机制观察与使用原位SEM在样品表面上进行的观察相关，以获得一组互补的信息，从而更好地理解这种新型合金的失效机制。
Alloy 709 is a novel austenitic stainless steel with high temperature creep strength, weldability, and corrosion resistance. These properties make the material suitable for applications in the structure of next-generation nuclear power plants. Enduring high temperatures for an extended period of time in the harsh environments of a nuclear power plant results in thermal aging of the material. Therefore, it is imperative to study the effect of thermal aging on the microstructure and mechanical properties of Alloy 709 before its application in the next generation power plants. In this study, hot-processed (forged + rolled), annealed and quenched ingots of Alloy 709 are aged at 650 °C for 2000 h in air and then tested at various temperatures up to 850 °C in an in-situ heating-loading Scanning Electron Microscope (SEM) equipped with Energy Dispersive Spectroscopy (EDS) and Electron Backscatter Diffraction (EBSD). The effect of testing temperature and aging on microstructural evolutions during tensile testing of as-received and aged samples are studied. Both as-received and aged samples displayed serrations and drop in ductility at elevated temperatures, due to the effect of dynamic strain aging (DSA). The occurrence of DSA activity was found within temperatures range of 500 °C–750 °C in as-received and 550 °C - 650 °C in aged samples. The aged samples showed less elongation accompanied by shallower dimples on the fractured surface, indicating less ductile failure mechanism compared to as-received samples. Failure mechanism observations on the fracture surface using SEM fractography are correlated to the observations made on the sample surface using in-situ SEM to achieve a complementary set of information to better understand the failure mechanism of this novel alloy.
登录
查看更多内容
Inconel 718 高温合金动态应变时效表现的观察
DOI：
--
发表时间：
2018
期刊：
Materials Science Forum
影响因子：
--
作者：
M. C. Rezende;L. S. Araújo;S. B. Gabriel;J. Dille;L. H. de Almeida
通讯作者：
L. H. de Almeida
DOI：
10.1016/j.msea.2018.06.089
发表时间：
2018
期刊：
Materials Science and Engineering: A
影响因子：
--
作者：
S. Upadhayay;Hangyue Li;P. Bowen;A. Rabiei
通讯作者：
A. Rabiei
709合金不同温度下的变形显微组织和拉伸性能
影响因子：
8.4
作者：
Ding R
通讯作者：
Ding R
影响因子：
4.7
作者：
Ding, Rengen;Yan, Jin;Bowen, Paul
通讯作者：
Bowen, Paul
单调和循环加载下变质9Cr-1Mo钢的动态应变时效行为
DOI：
--
发表时间：
2017
期刊：
影响因子：
--
作者：
N. Srinivas;Preeti Verma;Vakil Singh
通讯作者：
Vakil Singh