In situ observation of intergranular crack nucleation in a grain boundary controlled austenitic stainless steel
In situ observation of intergranular crack nucleation in a grain boundary controlled austenitic stainless steel
复制标题
DOI：
10.1111/j.1365-2818.2009.03133.x
复制
发表时间：
2009-03
影响因子：
2
通讯作者：
S. Rahimi;D. Engelberg;J. Duff;T. Marrow
中科院分区：
文献类型：
--
作者：
S. Rahimi;D. Engelberg;J. Duff;T. Marrow
晶界工程已被提出来提高敏化奥氏体不锈钢在侵蚀性环境中的寿命性能。微观结构阻力的增加通常与孪晶 (Σ3) 晶界比例的增加有关，但其他晶界的性质和作用存在不确定性。为了开发应力腐蚀裂纹成核的预测模型，需要更多关于晶界晶体学以及晶界平面及其周围晶粒的方向如何影响裂纹发展的信息。数字图像关联与电子背散射衍射相结合已用于表征微观结构并原位观察热机械处理的 304 型不锈钢中短应力腐蚀裂纹的成核和扩展。裂纹路径及其扩展速率已被确定，并发现其受到微观结构的影响。
Grain boundary engineering has been proposed to increase the lifetime performance of sensitized austenitic stainless steel in aggressive environments. Increased microstructure resistance is typically associated with higher fractions of twin (Σ3) grain boundaries, but there is uncertainty about the properties and role of other boundaries. To develop predictive models for stress corrosion crack nucleation, more information is required about how grain boundary crystallography and the orientations of the grain boundary plane and its surrounding grains affect crack development. Digital image correlation combined with electron backscatter diffraction has been used to characterize the microstructure and to observe, in situ, the nucleation and propagation of short stress corrosion cracks in thermo‐mechanically processed type 304 stainless steel. The crack path and its growth rate have been determined and are found to be influenced by the microstructure.